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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
bc0c38d1 | 15 | #include <linux/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
4c11d7ae | 23 | #include <linux/pagemap.h> |
bc0c38d1 SR |
24 | #include <linux/hardirq.h> |
25 | #include <linux/linkage.h> | |
26 | #include <linux/uaccess.h> | |
2cadf913 | 27 | #include <linux/kprobes.h> |
bc0c38d1 SR |
28 | #include <linux/ftrace.h> |
29 | #include <linux/module.h> | |
30 | #include <linux/percpu.h> | |
2cadf913 | 31 | #include <linux/splice.h> |
3f5a54e3 | 32 | #include <linux/kdebug.h> |
bc0c38d1 SR |
33 | #include <linux/ctype.h> |
34 | #include <linux/init.h> | |
2a2cc8f7 | 35 | #include <linux/poll.h> |
bc0c38d1 SR |
36 | #include <linux/gfp.h> |
37 | #include <linux/fs.h> | |
86387f7e | 38 | |
bc0c38d1 | 39 | #include "trace.h" |
f0868d1e | 40 | #include "trace_output.h" |
bc0c38d1 | 41 | |
3928a8a2 SR |
42 | #define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE) |
43 | ||
745b1626 | 44 | unsigned long __read_mostly tracing_max_latency; |
bc0c38d1 SR |
45 | unsigned long __read_mostly tracing_thresh; |
46 | ||
8e1b82e0 FW |
47 | /* |
48 | * We need to change this state when a selftest is running. | |
ff32504f FW |
49 | * A selftest will lurk into the ring-buffer to count the |
50 | * entries inserted during the selftest although some concurrent | |
51 | * insertions into the ring-buffer such as ftrace_printk could occurred | |
52 | * at the same time, giving false positive or negative results. | |
53 | */ | |
8e1b82e0 | 54 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 55 | |
b2821ae6 SR |
56 | /* |
57 | * If a tracer is running, we do not want to run SELFTEST. | |
58 | */ | |
59 | static bool __read_mostly tracing_selftest_disabled; | |
60 | ||
adf9f195 FW |
61 | /* For tracers that don't implement custom flags */ |
62 | static struct tracer_opt dummy_tracer_opt[] = { | |
63 | { } | |
64 | }; | |
65 | ||
66 | static struct tracer_flags dummy_tracer_flags = { | |
67 | .val = 0, | |
68 | .opts = dummy_tracer_opt | |
69 | }; | |
70 | ||
71 | static int dummy_set_flag(u32 old_flags, u32 bit, int set) | |
72 | { | |
73 | return 0; | |
74 | } | |
0f048701 SR |
75 | |
76 | /* | |
77 | * Kill all tracing for good (never come back). | |
78 | * It is initialized to 1 but will turn to zero if the initialization | |
79 | * of the tracer is successful. But that is the only place that sets | |
80 | * this back to zero. | |
81 | */ | |
4fd27358 | 82 | static int tracing_disabled = 1; |
0f048701 | 83 | |
d769041f SR |
84 | static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled); |
85 | ||
86 | static inline void ftrace_disable_cpu(void) | |
87 | { | |
88 | preempt_disable(); | |
89 | local_inc(&__get_cpu_var(ftrace_cpu_disabled)); | |
90 | } | |
91 | ||
92 | static inline void ftrace_enable_cpu(void) | |
93 | { | |
94 | local_dec(&__get_cpu_var(ftrace_cpu_disabled)); | |
95 | preempt_enable(); | |
96 | } | |
97 | ||
9e01c1b7 | 98 | static cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 99 | |
b04cc6b1 FW |
100 | /* Define which cpu buffers are currently read in trace_pipe */ |
101 | static cpumask_var_t tracing_reader_cpumask; | |
102 | ||
ab46428c | 103 | #define for_each_tracing_cpu(cpu) \ |
9e01c1b7 | 104 | for_each_cpu(cpu, tracing_buffer_mask) |
ab46428c | 105 | |
944ac425 SR |
106 | /* |
107 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
108 | * | |
109 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
110 | * is set, then ftrace_dump is called. This will output the contents | |
111 | * of the ftrace buffers to the console. This is very useful for | |
112 | * capturing traces that lead to crashes and outputing it to a | |
113 | * serial console. | |
114 | * | |
115 | * It is default off, but you can enable it with either specifying | |
116 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
117 | * /proc/sys/kernel/ftrace_dump_on_oops to true. | |
118 | */ | |
119 | int ftrace_dump_on_oops; | |
120 | ||
b2821ae6 SR |
121 | static int tracing_set_tracer(const char *buf); |
122 | ||
123 | #define BOOTUP_TRACER_SIZE 100 | |
124 | static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata; | |
125 | static char *default_bootup_tracer; | |
d9e54076 PZ |
126 | |
127 | static int __init set_ftrace(char *str) | |
128 | { | |
b2821ae6 SR |
129 | strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE); |
130 | default_bootup_tracer = bootup_tracer_buf; | |
d9e54076 PZ |
131 | return 1; |
132 | } | |
b2821ae6 | 133 | __setup("ftrace=", set_ftrace); |
d9e54076 | 134 | |
944ac425 SR |
135 | static int __init set_ftrace_dump_on_oops(char *str) |
136 | { | |
137 | ftrace_dump_on_oops = 1; | |
138 | return 1; | |
139 | } | |
140 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 141 | |
72829bc3 | 142 | long |
bc0c38d1 SR |
143 | ns2usecs(cycle_t nsec) |
144 | { | |
145 | nsec += 500; | |
146 | do_div(nsec, 1000); | |
147 | return nsec; | |
148 | } | |
149 | ||
e309b41d | 150 | cycle_t ftrace_now(int cpu) |
750ed1a4 | 151 | { |
3928a8a2 SR |
152 | u64 ts = ring_buffer_time_stamp(cpu); |
153 | ring_buffer_normalize_time_stamp(cpu, &ts); | |
154 | return ts; | |
750ed1a4 IM |
155 | } |
156 | ||
4fcdae83 SR |
157 | /* |
158 | * The global_trace is the descriptor that holds the tracing | |
159 | * buffers for the live tracing. For each CPU, it contains | |
160 | * a link list of pages that will store trace entries. The | |
161 | * page descriptor of the pages in the memory is used to hold | |
162 | * the link list by linking the lru item in the page descriptor | |
163 | * to each of the pages in the buffer per CPU. | |
164 | * | |
165 | * For each active CPU there is a data field that holds the | |
166 | * pages for the buffer for that CPU. Each CPU has the same number | |
167 | * of pages allocated for its buffer. | |
168 | */ | |
bc0c38d1 SR |
169 | static struct trace_array global_trace; |
170 | ||
171 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
172 | ||
4fcdae83 SR |
173 | /* |
174 | * The max_tr is used to snapshot the global_trace when a maximum | |
175 | * latency is reached. Some tracers will use this to store a maximum | |
176 | * trace while it continues examining live traces. | |
177 | * | |
178 | * The buffers for the max_tr are set up the same as the global_trace. | |
179 | * When a snapshot is taken, the link list of the max_tr is swapped | |
180 | * with the link list of the global_trace and the buffers are reset for | |
181 | * the global_trace so the tracing can continue. | |
182 | */ | |
bc0c38d1 SR |
183 | static struct trace_array max_tr; |
184 | ||
185 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
186 | ||
4fcdae83 | 187 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 188 | static int tracer_enabled = 1; |
4fcdae83 | 189 | |
9036990d SR |
190 | /** |
191 | * tracing_is_enabled - return tracer_enabled status | |
192 | * | |
193 | * This function is used by other tracers to know the status | |
194 | * of the tracer_enabled flag. Tracers may use this function | |
195 | * to know if it should enable their features when starting | |
196 | * up. See irqsoff tracer for an example (start_irqsoff_tracer). | |
197 | */ | |
198 | int tracing_is_enabled(void) | |
199 | { | |
200 | return tracer_enabled; | |
201 | } | |
202 | ||
4fcdae83 | 203 | /* |
3928a8a2 SR |
204 | * trace_buf_size is the size in bytes that is allocated |
205 | * for a buffer. Note, the number of bytes is always rounded | |
206 | * to page size. | |
3f5a54e3 SR |
207 | * |
208 | * This number is purposely set to a low number of 16384. | |
209 | * If the dump on oops happens, it will be much appreciated | |
210 | * to not have to wait for all that output. Anyway this can be | |
211 | * boot time and run time configurable. | |
4fcdae83 | 212 | */ |
3928a8a2 | 213 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 214 | |
3928a8a2 | 215 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 216 | |
4fcdae83 | 217 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 218 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
219 | |
220 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 221 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
222 | |
223 | /* | |
224 | * max_tracer_type_len is used to simplify the allocating of | |
225 | * buffers to read userspace tracer names. We keep track of | |
226 | * the longest tracer name registered. | |
227 | */ | |
bc0c38d1 SR |
228 | static int max_tracer_type_len; |
229 | ||
4fcdae83 SR |
230 | /* |
231 | * trace_types_lock is used to protect the trace_types list. | |
232 | * This lock is also used to keep user access serialized. | |
233 | * Accesses from userspace will grab this lock while userspace | |
234 | * activities happen inside the kernel. | |
235 | */ | |
bc0c38d1 | 236 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
237 | |
238 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
239 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
240 | ||
ee6bce52 | 241 | /* trace_flags holds trace_options default values */ |
12ef7d44 | 242 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | |
c4a8e8be | 243 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO; |
4e655519 | 244 | |
4fcdae83 SR |
245 | /** |
246 | * trace_wake_up - wake up tasks waiting for trace input | |
247 | * | |
248 | * Simply wakes up any task that is blocked on the trace_wait | |
249 | * queue. These is used with trace_poll for tasks polling the trace. | |
250 | */ | |
4e655519 IM |
251 | void trace_wake_up(void) |
252 | { | |
017730c1 IM |
253 | /* |
254 | * The runqueue_is_locked() can fail, but this is the best we | |
255 | * have for now: | |
256 | */ | |
257 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
258 | wake_up(&trace_wait); |
259 | } | |
bc0c38d1 | 260 | |
3928a8a2 | 261 | static int __init set_buf_size(char *str) |
bc0c38d1 | 262 | { |
3928a8a2 | 263 | unsigned long buf_size; |
c6caeeb1 SR |
264 | int ret; |
265 | ||
bc0c38d1 SR |
266 | if (!str) |
267 | return 0; | |
3928a8a2 | 268 | ret = strict_strtoul(str, 0, &buf_size); |
c6caeeb1 | 269 | /* nr_entries can not be zero */ |
3928a8a2 | 270 | if (ret < 0 || buf_size == 0) |
c6caeeb1 | 271 | return 0; |
3928a8a2 | 272 | trace_buf_size = buf_size; |
bc0c38d1 SR |
273 | return 1; |
274 | } | |
3928a8a2 | 275 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 276 | |
57f50be1 SR |
277 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
278 | { | |
279 | return nsecs / 1000; | |
280 | } | |
281 | ||
4fcdae83 | 282 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
283 | static const char *trace_options[] = { |
284 | "print-parent", | |
285 | "sym-offset", | |
286 | "sym-addr", | |
287 | "verbose", | |
f9896bf3 | 288 | "raw", |
5e3ca0ec | 289 | "hex", |
cb0f12aa | 290 | "bin", |
2a2cc8f7 | 291 | "block", |
86387f7e | 292 | "stacktrace", |
4ac3ba41 | 293 | "sched-tree", |
f09ce573 | 294 | "ftrace_printk", |
b2a866f9 | 295 | "ftrace_preempt", |
9f029e83 | 296 | "branch", |
12ef7d44 | 297 | "annotate", |
02b67518 | 298 | "userstacktrace", |
b54d3de9 | 299 | "sym-userobj", |
66896a85 | 300 | "printk-msg-only", |
c4a8e8be | 301 | "context-info", |
c032ef64 | 302 | "latency-format", |
bc0c38d1 SR |
303 | NULL |
304 | }; | |
305 | ||
4fcdae83 SR |
306 | /* |
307 | * ftrace_max_lock is used to protect the swapping of buffers | |
308 | * when taking a max snapshot. The buffers themselves are | |
309 | * protected by per_cpu spinlocks. But the action of the swap | |
310 | * needs its own lock. | |
311 | * | |
312 | * This is defined as a raw_spinlock_t in order to help | |
313 | * with performance when lockdep debugging is enabled. | |
314 | */ | |
92205c23 SR |
315 | static raw_spinlock_t ftrace_max_lock = |
316 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
317 | |
318 | /* | |
319 | * Copy the new maximum trace into the separate maximum-trace | |
320 | * structure. (this way the maximum trace is permanently saved, | |
321 | * for later retrieval via /debugfs/tracing/latency_trace) | |
322 | */ | |
e309b41d | 323 | static void |
bc0c38d1 SR |
324 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
325 | { | |
326 | struct trace_array_cpu *data = tr->data[cpu]; | |
327 | ||
328 | max_tr.cpu = cpu; | |
329 | max_tr.time_start = data->preempt_timestamp; | |
330 | ||
331 | data = max_tr.data[cpu]; | |
332 | data->saved_latency = tracing_max_latency; | |
333 | ||
334 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
335 | data->pid = tsk->pid; | |
b6dff3ec | 336 | data->uid = task_uid(tsk); |
bc0c38d1 SR |
337 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
338 | data->policy = tsk->policy; | |
339 | data->rt_priority = tsk->rt_priority; | |
340 | ||
341 | /* record this tasks comm */ | |
af513098 | 342 | tracing_record_cmdline(tsk); |
bc0c38d1 SR |
343 | } |
344 | ||
6c6c2796 PP |
345 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) |
346 | { | |
347 | int len; | |
348 | int ret; | |
349 | ||
2dc5d12b SR |
350 | if (!cnt) |
351 | return 0; | |
352 | ||
6c6c2796 PP |
353 | if (s->len <= s->readpos) |
354 | return -EBUSY; | |
355 | ||
356 | len = s->len - s->readpos; | |
357 | if (cnt > len) | |
358 | cnt = len; | |
359 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
2dc5d12b | 360 | if (ret == cnt) |
6c6c2796 PP |
361 | return -EFAULT; |
362 | ||
2dc5d12b SR |
363 | cnt -= ret; |
364 | ||
e74da523 | 365 | s->readpos += cnt; |
6c6c2796 | 366 | return cnt; |
214023c3 SR |
367 | } |
368 | ||
3c56819b EGM |
369 | ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
370 | { | |
371 | int len; | |
372 | void *ret; | |
373 | ||
374 | if (s->len <= s->readpos) | |
375 | return -EBUSY; | |
376 | ||
377 | len = s->len - s->readpos; | |
378 | if (cnt > len) | |
379 | cnt = len; | |
380 | ret = memcpy(buf, s->buffer + s->readpos, cnt); | |
381 | if (!ret) | |
382 | return -EFAULT; | |
383 | ||
e74da523 | 384 | s->readpos += cnt; |
3c56819b EGM |
385 | return cnt; |
386 | } | |
387 | ||
e309b41d | 388 | static void |
214023c3 SR |
389 | trace_print_seq(struct seq_file *m, struct trace_seq *s) |
390 | { | |
391 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
392 | ||
393 | s->buffer[len] = 0; | |
394 | seq_puts(m, s->buffer); | |
395 | ||
f9520750 | 396 | trace_seq_init(s); |
214023c3 SR |
397 | } |
398 | ||
4fcdae83 SR |
399 | /** |
400 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
401 | * @tr: tracer | |
402 | * @tsk: the task with the latency | |
403 | * @cpu: The cpu that initiated the trace. | |
404 | * | |
405 | * Flip the buffers between the @tr and the max_tr and record information | |
406 | * about which task was the cause of this latency. | |
407 | */ | |
e309b41d | 408 | void |
bc0c38d1 SR |
409 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
410 | { | |
3928a8a2 | 411 | struct ring_buffer *buf = tr->buffer; |
bc0c38d1 | 412 | |
4c11d7ae | 413 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 414 | __raw_spin_lock(&ftrace_max_lock); |
3928a8a2 SR |
415 | |
416 | tr->buffer = max_tr.buffer; | |
417 | max_tr.buffer = buf; | |
418 | ||
d769041f | 419 | ftrace_disable_cpu(); |
3928a8a2 | 420 | ring_buffer_reset(tr->buffer); |
d769041f | 421 | ftrace_enable_cpu(); |
bc0c38d1 SR |
422 | |
423 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 424 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
425 | } |
426 | ||
427 | /** | |
428 | * update_max_tr_single - only copy one trace over, and reset the rest | |
429 | * @tr - tracer | |
430 | * @tsk - task with the latency | |
431 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
432 | * |
433 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 434 | */ |
e309b41d | 435 | void |
bc0c38d1 SR |
436 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
437 | { | |
3928a8a2 | 438 | int ret; |
bc0c38d1 | 439 | |
4c11d7ae | 440 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 441 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 442 | |
d769041f SR |
443 | ftrace_disable_cpu(); |
444 | ||
3928a8a2 SR |
445 | ring_buffer_reset(max_tr.buffer); |
446 | ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu); | |
447 | ||
d769041f SR |
448 | ftrace_enable_cpu(); |
449 | ||
97b17efe | 450 | WARN_ON_ONCE(ret && ret != -EAGAIN); |
bc0c38d1 SR |
451 | |
452 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 453 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
454 | } |
455 | ||
4fcdae83 SR |
456 | /** |
457 | * register_tracer - register a tracer with the ftrace system. | |
458 | * @type - the plugin for the tracer | |
459 | * | |
460 | * Register a new plugin tracer. | |
461 | */ | |
bc0c38d1 | 462 | int register_tracer(struct tracer *type) |
e7669b8e HE |
463 | __releases(kernel_lock) |
464 | __acquires(kernel_lock) | |
bc0c38d1 SR |
465 | { |
466 | struct tracer *t; | |
467 | int len; | |
468 | int ret = 0; | |
469 | ||
470 | if (!type->name) { | |
471 | pr_info("Tracer must have a name\n"); | |
472 | return -1; | |
473 | } | |
474 | ||
86fa2f60 IM |
475 | /* |
476 | * When this gets called we hold the BKL which means that | |
477 | * preemption is disabled. Various trace selftests however | |
478 | * need to disable and enable preemption for successful tests. | |
479 | * So we drop the BKL here and grab it after the tests again. | |
480 | */ | |
481 | unlock_kernel(); | |
bc0c38d1 | 482 | mutex_lock(&trace_types_lock); |
86fa2f60 | 483 | |
8e1b82e0 FW |
484 | tracing_selftest_running = true; |
485 | ||
bc0c38d1 SR |
486 | for (t = trace_types; t; t = t->next) { |
487 | if (strcmp(type->name, t->name) == 0) { | |
488 | /* already found */ | |
489 | pr_info("Trace %s already registered\n", | |
490 | type->name); | |
491 | ret = -1; | |
492 | goto out; | |
493 | } | |
494 | } | |
495 | ||
adf9f195 FW |
496 | if (!type->set_flag) |
497 | type->set_flag = &dummy_set_flag; | |
498 | if (!type->flags) | |
499 | type->flags = &dummy_tracer_flags; | |
500 | else | |
501 | if (!type->flags->opts) | |
502 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 FW |
503 | if (!type->wait_pipe) |
504 | type->wait_pipe = default_wait_pipe; | |
505 | ||
adf9f195 | 506 | |
60a11774 | 507 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
b2821ae6 | 508 | if (type->selftest && !tracing_selftest_disabled) { |
60a11774 | 509 | struct tracer *saved_tracer = current_trace; |
60a11774 | 510 | struct trace_array *tr = &global_trace; |
60a11774 | 511 | int i; |
ff32504f | 512 | |
60a11774 SR |
513 | /* |
514 | * Run a selftest on this tracer. | |
515 | * Here we reset the trace buffer, and set the current | |
516 | * tracer to be this tracer. The tracer can then run some | |
517 | * internal tracing to verify that everything is in order. | |
518 | * If we fail, we do not register this tracer. | |
519 | */ | |
86fa2f60 | 520 | for_each_tracing_cpu(i) |
3928a8a2 | 521 | tracing_reset(tr, i); |
86fa2f60 | 522 | |
60a11774 | 523 | current_trace = type; |
60a11774 SR |
524 | /* the test is responsible for initializing and enabling */ |
525 | pr_info("Testing tracer %s: ", type->name); | |
526 | ret = type->selftest(type, tr); | |
527 | /* the test is responsible for resetting too */ | |
528 | current_trace = saved_tracer; | |
60a11774 SR |
529 | if (ret) { |
530 | printk(KERN_CONT "FAILED!\n"); | |
531 | goto out; | |
532 | } | |
1d4db00a | 533 | /* Only reset on passing, to avoid touching corrupted buffers */ |
86fa2f60 | 534 | for_each_tracing_cpu(i) |
3928a8a2 | 535 | tracing_reset(tr, i); |
86fa2f60 | 536 | |
60a11774 SR |
537 | printk(KERN_CONT "PASSED\n"); |
538 | } | |
539 | #endif | |
540 | ||
bc0c38d1 SR |
541 | type->next = trace_types; |
542 | trace_types = type; | |
543 | len = strlen(type->name); | |
544 | if (len > max_tracer_type_len) | |
545 | max_tracer_type_len = len; | |
60a11774 | 546 | |
bc0c38d1 | 547 | out: |
8e1b82e0 | 548 | tracing_selftest_running = false; |
bc0c38d1 SR |
549 | mutex_unlock(&trace_types_lock); |
550 | ||
dac74940 SR |
551 | if (ret || !default_bootup_tracer) |
552 | goto out_unlock; | |
553 | ||
554 | if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE)) | |
555 | goto out_unlock; | |
556 | ||
557 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
558 | /* Do we want this tracer to start on bootup? */ | |
559 | tracing_set_tracer(type->name); | |
560 | default_bootup_tracer = NULL; | |
561 | /* disable other selftests, since this will break it. */ | |
562 | tracing_selftest_disabled = 1; | |
b2821ae6 | 563 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
564 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
565 | type->name); | |
b2821ae6 | 566 | #endif |
b2821ae6 | 567 | |
dac74940 | 568 | out_unlock: |
b2821ae6 | 569 | lock_kernel(); |
bc0c38d1 SR |
570 | return ret; |
571 | } | |
572 | ||
573 | void unregister_tracer(struct tracer *type) | |
574 | { | |
575 | struct tracer **t; | |
576 | int len; | |
577 | ||
578 | mutex_lock(&trace_types_lock); | |
579 | for (t = &trace_types; *t; t = &(*t)->next) { | |
580 | if (*t == type) | |
581 | goto found; | |
582 | } | |
583 | pr_info("Trace %s not registered\n", type->name); | |
584 | goto out; | |
585 | ||
586 | found: | |
587 | *t = (*t)->next; | |
b5db03c4 ACM |
588 | |
589 | if (type == current_trace && tracer_enabled) { | |
590 | tracer_enabled = 0; | |
591 | tracing_stop(); | |
592 | if (current_trace->stop) | |
593 | current_trace->stop(&global_trace); | |
594 | current_trace = &nop_trace; | |
595 | } | |
596 | ||
bc0c38d1 SR |
597 | if (strlen(type->name) != max_tracer_type_len) |
598 | goto out; | |
599 | ||
600 | max_tracer_type_len = 0; | |
601 | for (t = &trace_types; *t; t = &(*t)->next) { | |
602 | len = strlen((*t)->name); | |
603 | if (len > max_tracer_type_len) | |
604 | max_tracer_type_len = len; | |
605 | } | |
606 | out: | |
607 | mutex_unlock(&trace_types_lock); | |
608 | } | |
609 | ||
3928a8a2 | 610 | void tracing_reset(struct trace_array *tr, int cpu) |
bc0c38d1 | 611 | { |
d769041f | 612 | ftrace_disable_cpu(); |
3928a8a2 | 613 | ring_buffer_reset_cpu(tr->buffer, cpu); |
d769041f | 614 | ftrace_enable_cpu(); |
bc0c38d1 SR |
615 | } |
616 | ||
213cc060 PE |
617 | void tracing_reset_online_cpus(struct trace_array *tr) |
618 | { | |
619 | int cpu; | |
620 | ||
621 | tr->time_start = ftrace_now(tr->cpu); | |
622 | ||
623 | for_each_online_cpu(cpu) | |
624 | tracing_reset(tr, cpu); | |
625 | } | |
626 | ||
bc0c38d1 SR |
627 | #define SAVED_CMDLINES 128 |
628 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
629 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
630 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
631 | static int cmdline_idx; | |
efed792d | 632 | static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED; |
25b0b44a | 633 | |
25b0b44a | 634 | /* temporary disable recording */ |
4fd27358 | 635 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 SR |
636 | |
637 | static void trace_init_cmdlines(void) | |
638 | { | |
639 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
640 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
641 | cmdline_idx = 0; | |
642 | } | |
643 | ||
0f048701 SR |
644 | static int trace_stop_count; |
645 | static DEFINE_SPINLOCK(tracing_start_lock); | |
646 | ||
69bb54ec SR |
647 | /** |
648 | * ftrace_off_permanent - disable all ftrace code permanently | |
649 | * | |
650 | * This should only be called when a serious anomally has | |
651 | * been detected. This will turn off the function tracing, | |
652 | * ring buffers, and other tracing utilites. It takes no | |
653 | * locks and can be called from any context. | |
654 | */ | |
655 | void ftrace_off_permanent(void) | |
656 | { | |
657 | tracing_disabled = 1; | |
658 | ftrace_stop(); | |
659 | tracing_off_permanent(); | |
660 | } | |
661 | ||
0f048701 SR |
662 | /** |
663 | * tracing_start - quick start of the tracer | |
664 | * | |
665 | * If tracing is enabled but was stopped by tracing_stop, | |
666 | * this will start the tracer back up. | |
667 | */ | |
668 | void tracing_start(void) | |
669 | { | |
670 | struct ring_buffer *buffer; | |
671 | unsigned long flags; | |
672 | ||
673 | if (tracing_disabled) | |
674 | return; | |
675 | ||
676 | spin_lock_irqsave(&tracing_start_lock, flags); | |
b06a8301 SR |
677 | if (--trace_stop_count) { |
678 | if (trace_stop_count < 0) { | |
679 | /* Someone screwed up their debugging */ | |
680 | WARN_ON_ONCE(1); | |
681 | trace_stop_count = 0; | |
682 | } | |
0f048701 SR |
683 | goto out; |
684 | } | |
685 | ||
686 | ||
687 | buffer = global_trace.buffer; | |
688 | if (buffer) | |
689 | ring_buffer_record_enable(buffer); | |
690 | ||
691 | buffer = max_tr.buffer; | |
692 | if (buffer) | |
693 | ring_buffer_record_enable(buffer); | |
694 | ||
695 | ftrace_start(); | |
696 | out: | |
697 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
698 | } | |
699 | ||
700 | /** | |
701 | * tracing_stop - quick stop of the tracer | |
702 | * | |
703 | * Light weight way to stop tracing. Use in conjunction with | |
704 | * tracing_start. | |
705 | */ | |
706 | void tracing_stop(void) | |
707 | { | |
708 | struct ring_buffer *buffer; | |
709 | unsigned long flags; | |
710 | ||
711 | ftrace_stop(); | |
712 | spin_lock_irqsave(&tracing_start_lock, flags); | |
713 | if (trace_stop_count++) | |
714 | goto out; | |
715 | ||
716 | buffer = global_trace.buffer; | |
717 | if (buffer) | |
718 | ring_buffer_record_disable(buffer); | |
719 | ||
720 | buffer = max_tr.buffer; | |
721 | if (buffer) | |
722 | ring_buffer_record_disable(buffer); | |
723 | ||
724 | out: | |
725 | spin_unlock_irqrestore(&tracing_start_lock, flags); | |
726 | } | |
727 | ||
e309b41d | 728 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 729 | |
e309b41d | 730 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
731 | { |
732 | unsigned map; | |
733 | unsigned idx; | |
734 | ||
735 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
736 | return; | |
737 | ||
738 | /* | |
739 | * It's not the end of the world if we don't get | |
740 | * the lock, but we also don't want to spin | |
741 | * nor do we want to disable interrupts, | |
742 | * so if we miss here, then better luck next time. | |
743 | */ | |
efed792d | 744 | if (!__raw_spin_trylock(&trace_cmdline_lock)) |
bc0c38d1 SR |
745 | return; |
746 | ||
747 | idx = map_pid_to_cmdline[tsk->pid]; | |
748 | if (idx >= SAVED_CMDLINES) { | |
749 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
750 | ||
751 | map = map_cmdline_to_pid[idx]; | |
752 | if (map <= PID_MAX_DEFAULT) | |
753 | map_pid_to_cmdline[map] = (unsigned)-1; | |
754 | ||
755 | map_pid_to_cmdline[tsk->pid] = idx; | |
756 | ||
757 | cmdline_idx = idx; | |
758 | } | |
759 | ||
760 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
761 | ||
efed792d | 762 | __raw_spin_unlock(&trace_cmdline_lock); |
bc0c38d1 SR |
763 | } |
764 | ||
660c7f9b | 765 | char *trace_find_cmdline(int pid) |
bc0c38d1 SR |
766 | { |
767 | char *cmdline = "<...>"; | |
768 | unsigned map; | |
769 | ||
770 | if (!pid) | |
771 | return "<idle>"; | |
772 | ||
773 | if (pid > PID_MAX_DEFAULT) | |
774 | goto out; | |
775 | ||
776 | map = map_pid_to_cmdline[pid]; | |
777 | if (map >= SAVED_CMDLINES) | |
778 | goto out; | |
779 | ||
780 | cmdline = saved_cmdlines[map]; | |
781 | ||
782 | out: | |
783 | return cmdline; | |
784 | } | |
785 | ||
e309b41d | 786 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
787 | { |
788 | if (atomic_read(&trace_record_cmdline_disabled)) | |
789 | return; | |
790 | ||
791 | trace_save_cmdline(tsk); | |
792 | } | |
793 | ||
45dcd8b8 | 794 | void |
38697053 SR |
795 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
796 | int pc) | |
bc0c38d1 SR |
797 | { |
798 | struct task_struct *tsk = current; | |
bc0c38d1 | 799 | |
777e208d SR |
800 | entry->preempt_count = pc & 0xff; |
801 | entry->pid = (tsk) ? tsk->pid : 0; | |
b54d3de9 | 802 | entry->tgid = (tsk) ? tsk->tgid : 0; |
777e208d | 803 | entry->flags = |
9244489a | 804 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 805 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
806 | #else |
807 | TRACE_FLAG_IRQS_NOSUPPORT | | |
808 | #endif | |
bc0c38d1 SR |
809 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
810 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
811 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
812 | } | |
813 | ||
51a763dd ACM |
814 | struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr, |
815 | unsigned char type, | |
816 | unsigned long len, | |
817 | unsigned long flags, int pc) | |
818 | { | |
819 | struct ring_buffer_event *event; | |
820 | ||
821 | event = ring_buffer_lock_reserve(tr->buffer, len); | |
822 | if (event != NULL) { | |
823 | struct trace_entry *ent = ring_buffer_event_data(event); | |
824 | ||
825 | tracing_generic_entry_update(ent, flags, pc); | |
826 | ent->type = type; | |
827 | } | |
828 | ||
829 | return event; | |
830 | } | |
831 | static void ftrace_trace_stack(struct trace_array *tr, | |
832 | unsigned long flags, int skip, int pc); | |
833 | static void ftrace_trace_userstack(struct trace_array *tr, | |
834 | unsigned long flags, int pc); | |
835 | ||
836 | void trace_buffer_unlock_commit(struct trace_array *tr, | |
837 | struct ring_buffer_event *event, | |
838 | unsigned long flags, int pc) | |
839 | { | |
840 | ring_buffer_unlock_commit(tr->buffer, event); | |
841 | ||
842 | ftrace_trace_stack(tr, flags, 6, pc); | |
843 | ftrace_trace_userstack(tr, flags, pc); | |
844 | trace_wake_up(); | |
845 | } | |
846 | ||
ef5580d0 SR |
847 | struct ring_buffer_event * |
848 | trace_current_buffer_lock_reserve(unsigned char type, unsigned long len, | |
849 | unsigned long flags, int pc) | |
850 | { | |
851 | return trace_buffer_lock_reserve(&global_trace, | |
852 | type, len, flags, pc); | |
853 | } | |
854 | ||
855 | void trace_current_buffer_unlock_commit(struct ring_buffer_event *event, | |
856 | unsigned long flags, int pc) | |
857 | { | |
858 | return trace_buffer_unlock_commit(&global_trace, event, flags, pc); | |
859 | } | |
860 | ||
e309b41d | 861 | void |
7be42151 | 862 | trace_function(struct trace_array *tr, |
38697053 SR |
863 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
864 | int pc) | |
bc0c38d1 | 865 | { |
3928a8a2 | 866 | struct ring_buffer_event *event; |
777e208d | 867 | struct ftrace_entry *entry; |
bc0c38d1 | 868 | |
d769041f SR |
869 | /* If we are reading the ring buffer, don't trace */ |
870 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
871 | return; | |
872 | ||
51a763dd ACM |
873 | event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry), |
874 | flags, pc); | |
3928a8a2 SR |
875 | if (!event) |
876 | return; | |
877 | entry = ring_buffer_event_data(event); | |
777e208d SR |
878 | entry->ip = ip; |
879 | entry->parent_ip = parent_ip; | |
0a987751 | 880 | ring_buffer_unlock_commit(tr->buffer, event); |
bc0c38d1 SR |
881 | } |
882 | ||
fb52607a | 883 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
287b6e68 | 884 | static void __trace_graph_entry(struct trace_array *tr, |
287b6e68 FW |
885 | struct ftrace_graph_ent *trace, |
886 | unsigned long flags, | |
887 | int pc) | |
888 | { | |
889 | struct ring_buffer_event *event; | |
890 | struct ftrace_graph_ent_entry *entry; | |
287b6e68 FW |
891 | |
892 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
893 | return; | |
894 | ||
51a763dd ACM |
895 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT, |
896 | sizeof(*entry), flags, pc); | |
287b6e68 FW |
897 | if (!event) |
898 | return; | |
899 | entry = ring_buffer_event_data(event); | |
287b6e68 | 900 | entry->graph_ent = *trace; |
0a987751 | 901 | ring_buffer_unlock_commit(global_trace.buffer, event); |
287b6e68 FW |
902 | } |
903 | ||
904 | static void __trace_graph_return(struct trace_array *tr, | |
fb52607a | 905 | struct ftrace_graph_ret *trace, |
15e6cb36 FW |
906 | unsigned long flags, |
907 | int pc) | |
908 | { | |
909 | struct ring_buffer_event *event; | |
287b6e68 | 910 | struct ftrace_graph_ret_entry *entry; |
15e6cb36 FW |
911 | |
912 | if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled)))) | |
913 | return; | |
914 | ||
51a763dd ACM |
915 | event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET, |
916 | sizeof(*entry), flags, pc); | |
15e6cb36 FW |
917 | if (!event) |
918 | return; | |
919 | entry = ring_buffer_event_data(event); | |
287b6e68 | 920 | entry->ret = *trace; |
0a987751 | 921 | ring_buffer_unlock_commit(global_trace.buffer, event); |
15e6cb36 FW |
922 | } |
923 | #endif | |
924 | ||
e309b41d | 925 | void |
2e0f5761 | 926 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
38697053 SR |
927 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
928 | int pc) | |
2e0f5761 IM |
929 | { |
930 | if (likely(!atomic_read(&data->disabled))) | |
7be42151 | 931 | trace_function(tr, ip, parent_ip, flags, pc); |
2e0f5761 IM |
932 | } |
933 | ||
53614991 | 934 | static void __ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
935 | unsigned long flags, |
936 | int skip, int pc) | |
86387f7e | 937 | { |
c2c80529 | 938 | #ifdef CONFIG_STACKTRACE |
3928a8a2 | 939 | struct ring_buffer_event *event; |
777e208d | 940 | struct stack_entry *entry; |
86387f7e IM |
941 | struct stack_trace trace; |
942 | ||
51a763dd ACM |
943 | event = trace_buffer_lock_reserve(tr, TRACE_STACK, |
944 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
945 | if (!event) |
946 | return; | |
947 | entry = ring_buffer_event_data(event); | |
777e208d | 948 | memset(&entry->caller, 0, sizeof(entry->caller)); |
86387f7e IM |
949 | |
950 | trace.nr_entries = 0; | |
951 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
952 | trace.skip = skip; | |
777e208d | 953 | trace.entries = entry->caller; |
86387f7e IM |
954 | |
955 | save_stack_trace(&trace); | |
0a987751 | 956 | ring_buffer_unlock_commit(tr->buffer, event); |
c2c80529 | 957 | #endif |
f0a920d5 IM |
958 | } |
959 | ||
53614991 | 960 | static void ftrace_trace_stack(struct trace_array *tr, |
53614991 SR |
961 | unsigned long flags, |
962 | int skip, int pc) | |
963 | { | |
964 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
965 | return; | |
966 | ||
7be42151 | 967 | __ftrace_trace_stack(tr, flags, skip, pc); |
53614991 SR |
968 | } |
969 | ||
38697053 | 970 | void __trace_stack(struct trace_array *tr, |
38697053 | 971 | unsigned long flags, |
53614991 | 972 | int skip, int pc) |
38697053 | 973 | { |
7be42151 | 974 | __ftrace_trace_stack(tr, flags, skip, pc); |
38697053 SR |
975 | } |
976 | ||
02b67518 | 977 | static void ftrace_trace_userstack(struct trace_array *tr, |
7be42151 | 978 | unsigned long flags, int pc) |
02b67518 | 979 | { |
c7425acb | 980 | #ifdef CONFIG_STACKTRACE |
8d7c6a96 | 981 | struct ring_buffer_event *event; |
02b67518 TE |
982 | struct userstack_entry *entry; |
983 | struct stack_trace trace; | |
02b67518 TE |
984 | |
985 | if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) | |
986 | return; | |
987 | ||
51a763dd ACM |
988 | event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK, |
989 | sizeof(*entry), flags, pc); | |
02b67518 TE |
990 | if (!event) |
991 | return; | |
992 | entry = ring_buffer_event_data(event); | |
02b67518 TE |
993 | |
994 | memset(&entry->caller, 0, sizeof(entry->caller)); | |
995 | ||
996 | trace.nr_entries = 0; | |
997 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
998 | trace.skip = 0; | |
999 | trace.entries = entry->caller; | |
1000 | ||
1001 | save_stack_trace_user(&trace); | |
0a987751 | 1002 | ring_buffer_unlock_commit(tr->buffer, event); |
c7425acb | 1003 | #endif |
02b67518 TE |
1004 | } |
1005 | ||
4fd27358 HE |
1006 | #ifdef UNUSED |
1007 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 1008 | { |
7be42151 | 1009 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 1010 | } |
4fd27358 | 1011 | #endif /* UNUSED */ |
02b67518 | 1012 | |
38697053 | 1013 | static void |
7be42151 | 1014 | ftrace_trace_special(void *__tr, |
38697053 SR |
1015 | unsigned long arg1, unsigned long arg2, unsigned long arg3, |
1016 | int pc) | |
a4feb834 | 1017 | { |
3928a8a2 | 1018 | struct ring_buffer_event *event; |
a4feb834 | 1019 | struct trace_array *tr = __tr; |
777e208d | 1020 | struct special_entry *entry; |
a4feb834 | 1021 | |
51a763dd ACM |
1022 | event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL, |
1023 | sizeof(*entry), 0, pc); | |
3928a8a2 SR |
1024 | if (!event) |
1025 | return; | |
1026 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1027 | entry->arg1 = arg1; |
1028 | entry->arg2 = arg2; | |
1029 | entry->arg3 = arg3; | |
51a763dd | 1030 | trace_buffer_unlock_commit(tr, event, 0, pc); |
a4feb834 IM |
1031 | } |
1032 | ||
38697053 SR |
1033 | void |
1034 | __trace_special(void *__tr, void *__data, | |
1035 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1036 | { | |
7be42151 | 1037 | ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count()); |
38697053 SR |
1038 | } |
1039 | ||
e309b41d | 1040 | void |
bc0c38d1 | 1041 | tracing_sched_switch_trace(struct trace_array *tr, |
86387f7e IM |
1042 | struct task_struct *prev, |
1043 | struct task_struct *next, | |
38697053 | 1044 | unsigned long flags, int pc) |
bc0c38d1 | 1045 | { |
3928a8a2 | 1046 | struct ring_buffer_event *event; |
777e208d | 1047 | struct ctx_switch_entry *entry; |
bc0c38d1 | 1048 | |
51a763dd ACM |
1049 | event = trace_buffer_lock_reserve(tr, TRACE_CTX, |
1050 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1051 | if (!event) |
1052 | return; | |
1053 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1054 | entry->prev_pid = prev->pid; |
1055 | entry->prev_prio = prev->prio; | |
1056 | entry->prev_state = prev->state; | |
1057 | entry->next_pid = next->pid; | |
1058 | entry->next_prio = next->prio; | |
1059 | entry->next_state = next->state; | |
1060 | entry->next_cpu = task_cpu(next); | |
51a763dd | 1061 | trace_buffer_unlock_commit(tr, event, flags, pc); |
bc0c38d1 SR |
1062 | } |
1063 | ||
57422797 IM |
1064 | void |
1065 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
86387f7e IM |
1066 | struct task_struct *wakee, |
1067 | struct task_struct *curr, | |
38697053 | 1068 | unsigned long flags, int pc) |
57422797 | 1069 | { |
3928a8a2 | 1070 | struct ring_buffer_event *event; |
777e208d | 1071 | struct ctx_switch_entry *entry; |
57422797 | 1072 | |
51a763dd ACM |
1073 | event = trace_buffer_lock_reserve(tr, TRACE_WAKE, |
1074 | sizeof(*entry), flags, pc); | |
3928a8a2 SR |
1075 | if (!event) |
1076 | return; | |
1077 | entry = ring_buffer_event_data(event); | |
777e208d SR |
1078 | entry->prev_pid = curr->pid; |
1079 | entry->prev_prio = curr->prio; | |
1080 | entry->prev_state = curr->state; | |
1081 | entry->next_pid = wakee->pid; | |
1082 | entry->next_prio = wakee->prio; | |
1083 | entry->next_state = wakee->state; | |
1084 | entry->next_cpu = task_cpu(wakee); | |
6eaaa5d5 FW |
1085 | |
1086 | ring_buffer_unlock_commit(tr->buffer, event); | |
1087 | ftrace_trace_stack(tr, flags, 6, pc); | |
1088 | ftrace_trace_userstack(tr, flags, pc); | |
57422797 IM |
1089 | } |
1090 | ||
4902f884 SR |
1091 | void |
1092 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1093 | { | |
1094 | struct trace_array *tr = &global_trace; | |
1095 | struct trace_array_cpu *data; | |
5aa1ba6a | 1096 | unsigned long flags; |
4902f884 | 1097 | int cpu; |
38697053 | 1098 | int pc; |
4902f884 | 1099 | |
c76f0694 | 1100 | if (tracing_disabled) |
4902f884 SR |
1101 | return; |
1102 | ||
38697053 | 1103 | pc = preempt_count(); |
5aa1ba6a | 1104 | local_irq_save(flags); |
4902f884 SR |
1105 | cpu = raw_smp_processor_id(); |
1106 | data = tr->data[cpu]; | |
4902f884 | 1107 | |
5aa1ba6a | 1108 | if (likely(atomic_inc_return(&data->disabled) == 1)) |
7be42151 | 1109 | ftrace_trace_special(tr, arg1, arg2, arg3, pc); |
4902f884 | 1110 | |
5aa1ba6a SR |
1111 | atomic_dec(&data->disabled); |
1112 | local_irq_restore(flags); | |
4902f884 SR |
1113 | } |
1114 | ||
fb52607a | 1115 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER |
e49dc19c | 1116 | int trace_graph_entry(struct ftrace_graph_ent *trace) |
15e6cb36 FW |
1117 | { |
1118 | struct trace_array *tr = &global_trace; | |
1119 | struct trace_array_cpu *data; | |
1120 | unsigned long flags; | |
1121 | long disabled; | |
1122 | int cpu; | |
1123 | int pc; | |
1124 | ||
804a6851 SR |
1125 | if (!ftrace_trace_task(current)) |
1126 | return 0; | |
1127 | ||
ea4e2bc4 SR |
1128 | if (!ftrace_graph_addr(trace->func)) |
1129 | return 0; | |
1130 | ||
a5e25883 | 1131 | local_irq_save(flags); |
15e6cb36 FW |
1132 | cpu = raw_smp_processor_id(); |
1133 | data = tr->data[cpu]; | |
1134 | disabled = atomic_inc_return(&data->disabled); | |
1135 | if (likely(disabled == 1)) { | |
1136 | pc = preempt_count(); | |
7be42151 | 1137 | __trace_graph_entry(tr, trace, flags, pc); |
287b6e68 | 1138 | } |
ea4e2bc4 SR |
1139 | /* Only do the atomic if it is not already set */ |
1140 | if (!test_tsk_trace_graph(current)) | |
1141 | set_tsk_trace_graph(current); | |
287b6e68 | 1142 | atomic_dec(&data->disabled); |
a5e25883 | 1143 | local_irq_restore(flags); |
e49dc19c SR |
1144 | |
1145 | return 1; | |
287b6e68 FW |
1146 | } |
1147 | ||
1148 | void trace_graph_return(struct ftrace_graph_ret *trace) | |
1149 | { | |
1150 | struct trace_array *tr = &global_trace; | |
1151 | struct trace_array_cpu *data; | |
1152 | unsigned long flags; | |
1153 | long disabled; | |
1154 | int cpu; | |
1155 | int pc; | |
1156 | ||
a5e25883 | 1157 | local_irq_save(flags); |
287b6e68 FW |
1158 | cpu = raw_smp_processor_id(); |
1159 | data = tr->data[cpu]; | |
1160 | disabled = atomic_inc_return(&data->disabled); | |
1161 | if (likely(disabled == 1)) { | |
1162 | pc = preempt_count(); | |
7be42151 | 1163 | __trace_graph_return(tr, trace, flags, pc); |
15e6cb36 | 1164 | } |
ea4e2bc4 SR |
1165 | if (!trace->depth) |
1166 | clear_tsk_trace_graph(current); | |
15e6cb36 | 1167 | atomic_dec(&data->disabled); |
a5e25883 | 1168 | local_irq_restore(flags); |
15e6cb36 | 1169 | } |
fb52607a | 1170 | #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |
15e6cb36 | 1171 | |
bc0c38d1 SR |
1172 | enum trace_file_type { |
1173 | TRACE_FILE_LAT_FMT = 1, | |
12ef7d44 | 1174 | TRACE_FILE_ANNOTATE = 2, |
bc0c38d1 SR |
1175 | }; |
1176 | ||
e2ac8ef5 | 1177 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 1178 | { |
d769041f SR |
1179 | /* Don't allow ftrace to trace into the ring buffers */ |
1180 | ftrace_disable_cpu(); | |
1181 | ||
5a90f577 | 1182 | iter->idx++; |
d769041f SR |
1183 | if (iter->buffer_iter[iter->cpu]) |
1184 | ring_buffer_read(iter->buffer_iter[iter->cpu], NULL); | |
1185 | ||
1186 | ftrace_enable_cpu(); | |
5a90f577 SR |
1187 | } |
1188 | ||
e309b41d | 1189 | static struct trace_entry * |
3928a8a2 | 1190 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts) |
dd0e545f | 1191 | { |
3928a8a2 SR |
1192 | struct ring_buffer_event *event; |
1193 | struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu]; | |
dd0e545f | 1194 | |
d769041f SR |
1195 | /* Don't allow ftrace to trace into the ring buffers */ |
1196 | ftrace_disable_cpu(); | |
1197 | ||
1198 | if (buf_iter) | |
1199 | event = ring_buffer_iter_peek(buf_iter, ts); | |
1200 | else | |
1201 | event = ring_buffer_peek(iter->tr->buffer, cpu, ts); | |
1202 | ||
1203 | ftrace_enable_cpu(); | |
1204 | ||
3928a8a2 | 1205 | return event ? ring_buffer_event_data(event) : NULL; |
dd0e545f | 1206 | } |
d769041f | 1207 | |
dd0e545f | 1208 | static struct trace_entry * |
3928a8a2 | 1209 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts) |
bc0c38d1 | 1210 | { |
3928a8a2 | 1211 | struct ring_buffer *buffer = iter->tr->buffer; |
bc0c38d1 | 1212 | struct trace_entry *ent, *next = NULL; |
b04cc6b1 | 1213 | int cpu_file = iter->cpu_file; |
3928a8a2 | 1214 | u64 next_ts = 0, ts; |
bc0c38d1 SR |
1215 | int next_cpu = -1; |
1216 | int cpu; | |
1217 | ||
b04cc6b1 FW |
1218 | /* |
1219 | * If we are in a per_cpu trace file, don't bother by iterating over | |
1220 | * all cpu and peek directly. | |
1221 | */ | |
1222 | if (cpu_file > TRACE_PIPE_ALL_CPU) { | |
1223 | if (ring_buffer_empty_cpu(buffer, cpu_file)) | |
1224 | return NULL; | |
1225 | ent = peek_next_entry(iter, cpu_file, ent_ts); | |
1226 | if (ent_cpu) | |
1227 | *ent_cpu = cpu_file; | |
1228 | ||
1229 | return ent; | |
1230 | } | |
1231 | ||
ab46428c | 1232 | for_each_tracing_cpu(cpu) { |
dd0e545f | 1233 | |
3928a8a2 SR |
1234 | if (ring_buffer_empty_cpu(buffer, cpu)) |
1235 | continue; | |
dd0e545f | 1236 | |
3928a8a2 | 1237 | ent = peek_next_entry(iter, cpu, &ts); |
dd0e545f | 1238 | |
cdd31cd2 IM |
1239 | /* |
1240 | * Pick the entry with the smallest timestamp: | |
1241 | */ | |
3928a8a2 | 1242 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
1243 | next = ent; |
1244 | next_cpu = cpu; | |
3928a8a2 | 1245 | next_ts = ts; |
bc0c38d1 SR |
1246 | } |
1247 | } | |
1248 | ||
1249 | if (ent_cpu) | |
1250 | *ent_cpu = next_cpu; | |
1251 | ||
3928a8a2 SR |
1252 | if (ent_ts) |
1253 | *ent_ts = next_ts; | |
1254 | ||
bc0c38d1 SR |
1255 | return next; |
1256 | } | |
1257 | ||
dd0e545f | 1258 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
1259 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
1260 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 1261 | { |
3928a8a2 | 1262 | return __find_next_entry(iter, ent_cpu, ent_ts); |
dd0e545f SR |
1263 | } |
1264 | ||
1265 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1266 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1267 | { | |
3928a8a2 | 1268 | iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts); |
dd0e545f | 1269 | |
3928a8a2 | 1270 | if (iter->ent) |
e2ac8ef5 | 1271 | trace_iterator_increment(iter); |
dd0e545f | 1272 | |
3928a8a2 | 1273 | return iter->ent ? iter : NULL; |
b3806b43 | 1274 | } |
bc0c38d1 | 1275 | |
e309b41d | 1276 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 1277 | { |
d769041f SR |
1278 | /* Don't allow ftrace to trace into the ring buffers */ |
1279 | ftrace_disable_cpu(); | |
3928a8a2 | 1280 | ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts); |
d769041f | 1281 | ftrace_enable_cpu(); |
bc0c38d1 SR |
1282 | } |
1283 | ||
e309b41d | 1284 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1285 | { |
1286 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1287 | int i = (int)*pos; |
4e3c3333 | 1288 | void *ent; |
bc0c38d1 SR |
1289 | |
1290 | (*pos)++; | |
1291 | ||
1292 | /* can't go backwards */ | |
1293 | if (iter->idx > i) | |
1294 | return NULL; | |
1295 | ||
1296 | if (iter->idx < 0) | |
1297 | ent = find_next_entry_inc(iter); | |
1298 | else | |
1299 | ent = iter; | |
1300 | ||
1301 | while (ent && iter->idx < i) | |
1302 | ent = find_next_entry_inc(iter); | |
1303 | ||
1304 | iter->pos = *pos; | |
1305 | ||
bc0c38d1 SR |
1306 | return ent; |
1307 | } | |
1308 | ||
d7350c3f FW |
1309 | /* |
1310 | * No necessary locking here. The worst thing which can | |
1311 | * happen is loosing events consumed at the same time | |
1312 | * by a trace_pipe reader. | |
1313 | * Other than that, we don't risk to crash the ring buffer | |
1314 | * because it serializes the readers. | |
1315 | * | |
1316 | * The current tracer is copied to avoid a global locking | |
1317 | * all around. | |
1318 | */ | |
bc0c38d1 SR |
1319 | static void *s_start(struct seq_file *m, loff_t *pos) |
1320 | { | |
1321 | struct trace_iterator *iter = m->private; | |
d7350c3f | 1322 | static struct tracer *old_tracer; |
b04cc6b1 | 1323 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
1324 | void *p = NULL; |
1325 | loff_t l = 0; | |
3928a8a2 | 1326 | int cpu; |
bc0c38d1 | 1327 | |
d7350c3f | 1328 | /* copy the tracer to avoid using a global lock all around */ |
bc0c38d1 | 1329 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
1330 | if (unlikely(old_tracer != current_trace && current_trace)) { |
1331 | old_tracer = current_trace; | |
1332 | *iter->trace = *current_trace; | |
d15f57f2 | 1333 | } |
d7350c3f | 1334 | mutex_unlock(&trace_types_lock); |
bc0c38d1 SR |
1335 | |
1336 | atomic_inc(&trace_record_cmdline_disabled); | |
1337 | ||
bc0c38d1 SR |
1338 | if (*pos != iter->pos) { |
1339 | iter->ent = NULL; | |
1340 | iter->cpu = 0; | |
1341 | iter->idx = -1; | |
1342 | ||
d769041f SR |
1343 | ftrace_disable_cpu(); |
1344 | ||
b04cc6b1 FW |
1345 | if (cpu_file == TRACE_PIPE_ALL_CPU) { |
1346 | for_each_tracing_cpu(cpu) | |
1347 | ring_buffer_iter_reset(iter->buffer_iter[cpu]); | |
1348 | } else | |
1349 | ring_buffer_iter_reset(iter->buffer_iter[cpu_file]); | |
1350 | ||
bc0c38d1 | 1351 | |
d769041f SR |
1352 | ftrace_enable_cpu(); |
1353 | ||
bc0c38d1 SR |
1354 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
1355 | ; | |
1356 | ||
1357 | } else { | |
4c11d7ae | 1358 | l = *pos - 1; |
bc0c38d1 SR |
1359 | p = s_next(m, p, &l); |
1360 | } | |
1361 | ||
1362 | return p; | |
1363 | } | |
1364 | ||
1365 | static void s_stop(struct seq_file *m, void *p) | |
1366 | { | |
bc0c38d1 | 1367 | atomic_dec(&trace_record_cmdline_disabled); |
bc0c38d1 SR |
1368 | } |
1369 | ||
e309b41d | 1370 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1371 | { |
a6168353 ME |
1372 | seq_puts(m, "# _------=> CPU# \n"); |
1373 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1374 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1375 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1376 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1377 | seq_puts(m, "# |||| / \n"); | |
1378 | seq_puts(m, "# ||||| delay \n"); | |
1379 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1380 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1381 | } |
1382 | ||
e309b41d | 1383 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1384 | { |
a6168353 ME |
1385 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1386 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1387 | } |
1388 | ||
1389 | ||
e309b41d | 1390 | static void |
bc0c38d1 SR |
1391 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1392 | { | |
1393 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1394 | struct trace_array *tr = iter->tr; | |
1395 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1396 | struct tracer *type = current_trace; | |
3928a8a2 SR |
1397 | unsigned long total; |
1398 | unsigned long entries; | |
bc0c38d1 SR |
1399 | const char *name = "preemption"; |
1400 | ||
1401 | if (type) | |
1402 | name = type->name; | |
1403 | ||
3928a8a2 SR |
1404 | entries = ring_buffer_entries(iter->tr->buffer); |
1405 | total = entries + | |
1406 | ring_buffer_overruns(iter->tr->buffer); | |
bc0c38d1 SR |
1407 | |
1408 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1409 | name, UTS_RELEASE); | |
1410 | seq_puts(m, "-----------------------------------" | |
1411 | "---------------------------------\n"); | |
1412 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1413 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1414 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1415 | entries, |
4c11d7ae | 1416 | total, |
bc0c38d1 SR |
1417 | tr->cpu, |
1418 | #if defined(CONFIG_PREEMPT_NONE) | |
1419 | "server", | |
1420 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1421 | "desktop", | |
b5c21b45 | 1422 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1423 | "preempt", |
1424 | #else | |
1425 | "unknown", | |
1426 | #endif | |
1427 | /* These are reserved for later use */ | |
1428 | 0, 0, 0, 0); | |
1429 | #ifdef CONFIG_SMP | |
1430 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1431 | #else | |
1432 | seq_puts(m, ")\n"); | |
1433 | #endif | |
1434 | seq_puts(m, " -----------------\n"); | |
1435 | seq_printf(m, " | task: %.16s-%d " | |
1436 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1437 | data->comm, data->pid, data->uid, data->nice, | |
1438 | data->policy, data->rt_priority); | |
1439 | seq_puts(m, " -----------------\n"); | |
1440 | ||
1441 | if (data->critical_start) { | |
1442 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1443 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1444 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1445 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1446 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1447 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1448 | seq_puts(m, "\n"); |
1449 | } | |
1450 | ||
1451 | seq_puts(m, "\n"); | |
1452 | } | |
1453 | ||
a309720c SR |
1454 | static void test_cpu_buff_start(struct trace_iterator *iter) |
1455 | { | |
1456 | struct trace_seq *s = &iter->seq; | |
1457 | ||
12ef7d44 SR |
1458 | if (!(trace_flags & TRACE_ITER_ANNOTATE)) |
1459 | return; | |
1460 | ||
1461 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
1462 | return; | |
1463 | ||
4462344e | 1464 | if (cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
1465 | return; |
1466 | ||
4462344e | 1467 | cpumask_set_cpu(iter->cpu, iter->started); |
a309720c SR |
1468 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", iter->cpu); |
1469 | } | |
1470 | ||
c4a8e8be | 1471 | static enum print_line_t print_lat_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1472 | { |
214023c3 | 1473 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1474 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
f633cef0 | 1475 | struct trace_event *event; |
bc0c38d1 | 1476 | struct trace_entry *entry = iter->ent; |
dd0e545f | 1477 | |
a309720c SR |
1478 | test_cpu_buff_start(iter); |
1479 | ||
c4a8e8be FW |
1480 | event = ftrace_find_event(entry->type); |
1481 | ||
1482 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { | |
d9793bd8 ACM |
1483 | if (!trace_print_lat_context(iter)) |
1484 | goto partial; | |
bc0c38d1 | 1485 | } |
777e208d | 1486 | |
268ccda0 | 1487 | if (event) |
5fd73f86 | 1488 | return event->trace(iter, sym_flags); |
d9793bd8 ACM |
1489 | |
1490 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1491 | goto partial; | |
02b67518 | 1492 | |
2c4f035f | 1493 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1494 | partial: |
1495 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1496 | } |
1497 | ||
2c4f035f | 1498 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1499 | { |
214023c3 | 1500 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1501 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1502 | struct trace_entry *entry; |
f633cef0 | 1503 | struct trace_event *event; |
bc0c38d1 | 1504 | |
4e3c3333 | 1505 | entry = iter->ent; |
dd0e545f | 1506 | |
a309720c SR |
1507 | test_cpu_buff_start(iter); |
1508 | ||
c4a8e8be | 1509 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 1510 | |
c4a8e8be | 1511 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1512 | if (!trace_print_context(iter)) |
1513 | goto partial; | |
c4a8e8be | 1514 | } |
bc0c38d1 | 1515 | |
268ccda0 | 1516 | if (event) |
d9793bd8 ACM |
1517 | return event->trace(iter, sym_flags); |
1518 | ||
1519 | if (!trace_seq_printf(s, "Unknown type %d\n", entry->type)) | |
1520 | goto partial; | |
02b67518 | 1521 | |
2c4f035f | 1522 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1523 | partial: |
1524 | return TRACE_TYPE_PARTIAL_LINE; | |
bc0c38d1 SR |
1525 | } |
1526 | ||
2c4f035f | 1527 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1528 | { |
1529 | struct trace_seq *s = &iter->seq; | |
1530 | struct trace_entry *entry; | |
f633cef0 | 1531 | struct trace_event *event; |
f9896bf3 IM |
1532 | |
1533 | entry = iter->ent; | |
dd0e545f | 1534 | |
c4a8e8be | 1535 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
d9793bd8 ACM |
1536 | if (!trace_seq_printf(s, "%d %d %llu ", |
1537 | entry->pid, iter->cpu, iter->ts)) | |
1538 | goto partial; | |
c4a8e8be | 1539 | } |
f9896bf3 | 1540 | |
f633cef0 | 1541 | event = ftrace_find_event(entry->type); |
268ccda0 | 1542 | if (event) |
d9793bd8 ACM |
1543 | return event->raw(iter, 0); |
1544 | ||
1545 | if (!trace_seq_printf(s, "%d ?\n", entry->type)) | |
1546 | goto partial; | |
777e208d | 1547 | |
2c4f035f | 1548 | return TRACE_TYPE_HANDLED; |
d9793bd8 ACM |
1549 | partial: |
1550 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 IM |
1551 | } |
1552 | ||
2c4f035f | 1553 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1554 | { |
1555 | struct trace_seq *s = &iter->seq; | |
1556 | unsigned char newline = '\n'; | |
1557 | struct trace_entry *entry; | |
f633cef0 | 1558 | struct trace_event *event; |
5e3ca0ec IM |
1559 | |
1560 | entry = iter->ent; | |
dd0e545f | 1561 | |
c4a8e8be FW |
1562 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1563 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1564 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1565 | SEQ_PUT_HEX_FIELD_RET(s, iter->ts); | |
1566 | } | |
5e3ca0ec | 1567 | |
f633cef0 | 1568 | event = ftrace_find_event(entry->type); |
268ccda0 | 1569 | if (event) { |
ae7462b4 | 1570 | enum print_line_t ret = event->hex(iter, 0); |
d9793bd8 ACM |
1571 | if (ret != TRACE_TYPE_HANDLED) |
1572 | return ret; | |
1573 | } | |
7104f300 | 1574 | |
5e3ca0ec IM |
1575 | SEQ_PUT_FIELD_RET(s, newline); |
1576 | ||
2c4f035f | 1577 | return TRACE_TYPE_HANDLED; |
5e3ca0ec IM |
1578 | } |
1579 | ||
66896a85 FW |
1580 | static enum print_line_t print_printk_msg_only(struct trace_iterator *iter) |
1581 | { | |
1582 | struct trace_seq *s = &iter->seq; | |
1583 | struct trace_entry *entry = iter->ent; | |
1584 | struct print_entry *field; | |
1585 | int ret; | |
1586 | ||
1587 | trace_assign_type(field, entry); | |
1588 | ||
c4a8e8be | 1589 | ret = trace_seq_printf(s, "%s", field->buf); |
66896a85 FW |
1590 | if (!ret) |
1591 | return TRACE_TYPE_PARTIAL_LINE; | |
1592 | ||
66896a85 FW |
1593 | return TRACE_TYPE_HANDLED; |
1594 | } | |
1595 | ||
2c4f035f | 1596 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1597 | { |
1598 | struct trace_seq *s = &iter->seq; | |
1599 | struct trace_entry *entry; | |
f633cef0 | 1600 | struct trace_event *event; |
cb0f12aa IM |
1601 | |
1602 | entry = iter->ent; | |
dd0e545f | 1603 | |
c4a8e8be FW |
1604 | if (trace_flags & TRACE_ITER_CONTEXT_INFO) { |
1605 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1830b52d | 1606 | SEQ_PUT_FIELD_RET(s, iter->cpu); |
c4a8e8be FW |
1607 | SEQ_PUT_FIELD_RET(s, iter->ts); |
1608 | } | |
cb0f12aa | 1609 | |
f633cef0 | 1610 | event = ftrace_find_event(entry->type); |
268ccda0 | 1611 | return event ? event->binary(iter, 0) : TRACE_TYPE_HANDLED; |
cb0f12aa IM |
1612 | } |
1613 | ||
bc0c38d1 SR |
1614 | static int trace_empty(struct trace_iterator *iter) |
1615 | { | |
bc0c38d1 SR |
1616 | int cpu; |
1617 | ||
ab46428c | 1618 | for_each_tracing_cpu(cpu) { |
d769041f SR |
1619 | if (iter->buffer_iter[cpu]) { |
1620 | if (!ring_buffer_iter_empty(iter->buffer_iter[cpu])) | |
1621 | return 0; | |
1622 | } else { | |
1623 | if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu)) | |
1624 | return 0; | |
1625 | } | |
bc0c38d1 | 1626 | } |
d769041f | 1627 | |
797d3712 | 1628 | return 1; |
bc0c38d1 SR |
1629 | } |
1630 | ||
2c4f035f | 1631 | static enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 1632 | { |
2c4f035f FW |
1633 | enum print_line_t ret; |
1634 | ||
1635 | if (iter->trace && iter->trace->print_line) { | |
1636 | ret = iter->trace->print_line(iter); | |
1637 | if (ret != TRACE_TYPE_UNHANDLED) | |
1638 | return ret; | |
1639 | } | |
72829bc3 | 1640 | |
66896a85 FW |
1641 | if (iter->ent->type == TRACE_PRINT && |
1642 | trace_flags & TRACE_ITER_PRINTK && | |
1643 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
1644 | return print_printk_msg_only(iter); | |
1645 | ||
cb0f12aa IM |
1646 | if (trace_flags & TRACE_ITER_BIN) |
1647 | return print_bin_fmt(iter); | |
1648 | ||
5e3ca0ec IM |
1649 | if (trace_flags & TRACE_ITER_HEX) |
1650 | return print_hex_fmt(iter); | |
1651 | ||
f9896bf3 IM |
1652 | if (trace_flags & TRACE_ITER_RAW) |
1653 | return print_raw_fmt(iter); | |
1654 | ||
1655 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
c4a8e8be | 1656 | return print_lat_fmt(iter); |
f9896bf3 IM |
1657 | |
1658 | return print_trace_fmt(iter); | |
1659 | } | |
1660 | ||
bc0c38d1 SR |
1661 | static int s_show(struct seq_file *m, void *v) |
1662 | { | |
1663 | struct trace_iterator *iter = v; | |
1664 | ||
1665 | if (iter->ent == NULL) { | |
1666 | if (iter->tr) { | |
1667 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1668 | seq_puts(m, "#\n"); | |
1669 | } | |
8bba1bf5 MM |
1670 | if (iter->trace && iter->trace->print_header) |
1671 | iter->trace->print_header(m); | |
1672 | else if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
bc0c38d1 SR |
1673 | /* print nothing if the buffers are empty */ |
1674 | if (trace_empty(iter)) | |
1675 | return 0; | |
1676 | print_trace_header(m, iter); | |
1677 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1678 | print_lat_help_header(m); | |
1679 | } else { | |
1680 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1681 | print_func_help_header(m); | |
1682 | } | |
1683 | } else { | |
f9896bf3 | 1684 | print_trace_line(iter); |
214023c3 | 1685 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1686 | } |
1687 | ||
1688 | return 0; | |
1689 | } | |
1690 | ||
1691 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1692 | .start = s_start, |
1693 | .next = s_next, | |
1694 | .stop = s_stop, | |
1695 | .show = s_show, | |
bc0c38d1 SR |
1696 | }; |
1697 | ||
e309b41d | 1698 | static struct trace_iterator * |
85a2f9b4 | 1699 | __tracing_open(struct inode *inode, struct file *file) |
bc0c38d1 | 1700 | { |
b04cc6b1 | 1701 | long cpu_file = (long) inode->i_private; |
85a2f9b4 | 1702 | void *fail_ret = ERR_PTR(-ENOMEM); |
bc0c38d1 | 1703 | struct trace_iterator *iter; |
3928a8a2 | 1704 | struct seq_file *m; |
85a2f9b4 | 1705 | int cpu, ret; |
bc0c38d1 | 1706 | |
85a2f9b4 SR |
1707 | if (tracing_disabled) |
1708 | return ERR_PTR(-ENODEV); | |
60a11774 | 1709 | |
bc0c38d1 | 1710 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
85a2f9b4 SR |
1711 | if (!iter) |
1712 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 1713 | |
d7350c3f FW |
1714 | /* |
1715 | * We make a copy of the current tracer to avoid concurrent | |
1716 | * changes on it while we are reading. | |
1717 | */ | |
bc0c38d1 | 1718 | mutex_lock(&trace_types_lock); |
d7350c3f | 1719 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 1720 | if (!iter->trace) |
d7350c3f | 1721 | goto fail; |
85a2f9b4 | 1722 | |
d7350c3f FW |
1723 | if (current_trace) |
1724 | *iter->trace = *current_trace; | |
1725 | ||
bc0c38d1 SR |
1726 | if (current_trace && current_trace->print_max) |
1727 | iter->tr = &max_tr; | |
1728 | else | |
b04cc6b1 | 1729 | iter->tr = &global_trace; |
bc0c38d1 | 1730 | iter->pos = -1; |
d7350c3f | 1731 | mutex_init(&iter->mutex); |
b04cc6b1 | 1732 | iter->cpu_file = cpu_file; |
bc0c38d1 | 1733 | |
8bba1bf5 MM |
1734 | /* Notify the tracer early; before we stop tracing. */ |
1735 | if (iter->trace && iter->trace->open) | |
a93751ca | 1736 | iter->trace->open(iter); |
8bba1bf5 | 1737 | |
12ef7d44 SR |
1738 | /* Annotate start of buffers if we had overruns */ |
1739 | if (ring_buffer_overruns(iter->tr->buffer)) | |
1740 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
1741 | ||
b04cc6b1 FW |
1742 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) { |
1743 | for_each_tracing_cpu(cpu) { | |
12ef7d44 | 1744 | |
b04cc6b1 FW |
1745 | iter->buffer_iter[cpu] = |
1746 | ring_buffer_read_start(iter->tr->buffer, cpu); | |
d769041f | 1747 | |
b04cc6b1 FW |
1748 | if (!iter->buffer_iter[cpu]) |
1749 | goto fail_buffer; | |
1750 | } | |
1751 | } else { | |
1752 | cpu = iter->cpu_file; | |
3928a8a2 | 1753 | iter->buffer_iter[cpu] = |
b04cc6b1 | 1754 | ring_buffer_read_start(iter->tr->buffer, cpu); |
d769041f | 1755 | |
3928a8a2 | 1756 | if (!iter->buffer_iter[cpu]) |
b04cc6b1 | 1757 | goto fail; |
3928a8a2 SR |
1758 | } |
1759 | ||
bc0c38d1 | 1760 | /* TODO stop tracer */ |
85a2f9b4 SR |
1761 | ret = seq_open(file, &tracer_seq_ops); |
1762 | if (ret < 0) { | |
1763 | fail_ret = ERR_PTR(ret); | |
3928a8a2 | 1764 | goto fail_buffer; |
85a2f9b4 | 1765 | } |
bc0c38d1 | 1766 | |
3928a8a2 SR |
1767 | m = file->private_data; |
1768 | m->private = iter; | |
bc0c38d1 | 1769 | |
3928a8a2 | 1770 | /* stop the trace while dumping */ |
9036990d | 1771 | tracing_stop(); |
3928a8a2 | 1772 | |
bc0c38d1 SR |
1773 | mutex_unlock(&trace_types_lock); |
1774 | ||
bc0c38d1 | 1775 | return iter; |
3928a8a2 SR |
1776 | |
1777 | fail_buffer: | |
1778 | for_each_tracing_cpu(cpu) { | |
1779 | if (iter->buffer_iter[cpu]) | |
1780 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1781 | } | |
d7350c3f | 1782 | fail: |
3928a8a2 | 1783 | mutex_unlock(&trace_types_lock); |
d7350c3f | 1784 | kfree(iter->trace); |
0bb943c7 | 1785 | kfree(iter); |
3928a8a2 | 1786 | |
85a2f9b4 | 1787 | return fail_ret; |
bc0c38d1 SR |
1788 | } |
1789 | ||
1790 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1791 | { | |
60a11774 SR |
1792 | if (tracing_disabled) |
1793 | return -ENODEV; | |
1794 | ||
bc0c38d1 SR |
1795 | filp->private_data = inode->i_private; |
1796 | return 0; | |
1797 | } | |
1798 | ||
4fd27358 | 1799 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 SR |
1800 | { |
1801 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1802 | struct trace_iterator *iter = m->private; | |
3928a8a2 | 1803 | int cpu; |
bc0c38d1 SR |
1804 | |
1805 | mutex_lock(&trace_types_lock); | |
3928a8a2 SR |
1806 | for_each_tracing_cpu(cpu) { |
1807 | if (iter->buffer_iter[cpu]) | |
1808 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
1809 | } | |
1810 | ||
bc0c38d1 SR |
1811 | if (iter->trace && iter->trace->close) |
1812 | iter->trace->close(iter); | |
1813 | ||
1814 | /* reenable tracing if it was previously enabled */ | |
9036990d | 1815 | tracing_start(); |
bc0c38d1 SR |
1816 | mutex_unlock(&trace_types_lock); |
1817 | ||
1818 | seq_release(inode, file); | |
d7350c3f FW |
1819 | mutex_destroy(&iter->mutex); |
1820 | kfree(iter->trace); | |
bc0c38d1 SR |
1821 | kfree(iter); |
1822 | return 0; | |
1823 | } | |
1824 | ||
1825 | static int tracing_open(struct inode *inode, struct file *file) | |
1826 | { | |
85a2f9b4 SR |
1827 | struct trace_iterator *iter; |
1828 | int ret = 0; | |
bc0c38d1 | 1829 | |
85a2f9b4 SR |
1830 | iter = __tracing_open(inode, file); |
1831 | if (IS_ERR(iter)) | |
1832 | ret = PTR_ERR(iter); | |
c032ef64 | 1833 | else if (trace_flags & TRACE_ITER_LATENCY_FMT) |
bc0c38d1 SR |
1834 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
1835 | ||
1836 | return ret; | |
1837 | } | |
1838 | ||
e309b41d | 1839 | static void * |
bc0c38d1 SR |
1840 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1841 | { | |
1842 | struct tracer *t = m->private; | |
1843 | ||
1844 | (*pos)++; | |
1845 | ||
1846 | if (t) | |
1847 | t = t->next; | |
1848 | ||
1849 | m->private = t; | |
1850 | ||
1851 | return t; | |
1852 | } | |
1853 | ||
1854 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1855 | { | |
1856 | struct tracer *t = m->private; | |
1857 | loff_t l = 0; | |
1858 | ||
1859 | mutex_lock(&trace_types_lock); | |
1860 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1861 | ; | |
1862 | ||
1863 | return t; | |
1864 | } | |
1865 | ||
1866 | static void t_stop(struct seq_file *m, void *p) | |
1867 | { | |
1868 | mutex_unlock(&trace_types_lock); | |
1869 | } | |
1870 | ||
1871 | static int t_show(struct seq_file *m, void *v) | |
1872 | { | |
1873 | struct tracer *t = v; | |
1874 | ||
1875 | if (!t) | |
1876 | return 0; | |
1877 | ||
1878 | seq_printf(m, "%s", t->name); | |
1879 | if (t->next) | |
1880 | seq_putc(m, ' '); | |
1881 | else | |
1882 | seq_putc(m, '\n'); | |
1883 | ||
1884 | return 0; | |
1885 | } | |
1886 | ||
1887 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1888 | .start = t_start, |
1889 | .next = t_next, | |
1890 | .stop = t_stop, | |
1891 | .show = t_show, | |
bc0c38d1 SR |
1892 | }; |
1893 | ||
1894 | static int show_traces_open(struct inode *inode, struct file *file) | |
1895 | { | |
1896 | int ret; | |
1897 | ||
60a11774 SR |
1898 | if (tracing_disabled) |
1899 | return -ENODEV; | |
1900 | ||
bc0c38d1 SR |
1901 | ret = seq_open(file, &show_traces_seq_ops); |
1902 | if (!ret) { | |
1903 | struct seq_file *m = file->private_data; | |
1904 | m->private = trace_types; | |
1905 | } | |
1906 | ||
1907 | return ret; | |
1908 | } | |
1909 | ||
1910 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
1911 | .open = tracing_open, |
1912 | .read = seq_read, | |
1913 | .llseek = seq_lseek, | |
1914 | .release = tracing_release, | |
bc0c38d1 SR |
1915 | }; |
1916 | ||
bc0c38d1 | 1917 | static struct file_operations show_traces_fops = { |
c7078de1 IM |
1918 | .open = show_traces_open, |
1919 | .read = seq_read, | |
1920 | .release = seq_release, | |
1921 | }; | |
1922 | ||
36dfe925 IM |
1923 | /* |
1924 | * Only trace on a CPU if the bitmask is set: | |
1925 | */ | |
9e01c1b7 | 1926 | static cpumask_var_t tracing_cpumask; |
36dfe925 IM |
1927 | |
1928 | /* | |
1929 | * The tracer itself will not take this lock, but still we want | |
1930 | * to provide a consistent cpumask to user-space: | |
1931 | */ | |
1932 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
1933 | ||
1934 | /* | |
1935 | * Temporary storage for the character representation of the | |
1936 | * CPU bitmask (and one more byte for the newline): | |
1937 | */ | |
1938 | static char mask_str[NR_CPUS + 1]; | |
1939 | ||
c7078de1 IM |
1940 | static ssize_t |
1941 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
1942 | size_t count, loff_t *ppos) | |
1943 | { | |
36dfe925 | 1944 | int len; |
c7078de1 IM |
1945 | |
1946 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 1947 | |
9e01c1b7 | 1948 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); |
36dfe925 IM |
1949 | if (count - len < 2) { |
1950 | count = -EINVAL; | |
1951 | goto out_err; | |
1952 | } | |
1953 | len += sprintf(mask_str + len, "\n"); | |
1954 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
1955 | ||
1956 | out_err: | |
c7078de1 IM |
1957 | mutex_unlock(&tracing_cpumask_update_lock); |
1958 | ||
1959 | return count; | |
1960 | } | |
1961 | ||
1962 | static ssize_t | |
1963 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
1964 | size_t count, loff_t *ppos) | |
1965 | { | |
36dfe925 | 1966 | int err, cpu; |
9e01c1b7 RR |
1967 | cpumask_var_t tracing_cpumask_new; |
1968 | ||
1969 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
1970 | return -ENOMEM; | |
c7078de1 IM |
1971 | |
1972 | mutex_lock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 1973 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 1974 | if (err) |
36dfe925 IM |
1975 | goto err_unlock; |
1976 | ||
a5e25883 | 1977 | local_irq_disable(); |
92205c23 | 1978 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 1979 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
1980 | /* |
1981 | * Increase/decrease the disabled counter if we are | |
1982 | * about to flip a bit in the cpumask: | |
1983 | */ | |
9e01c1b7 RR |
1984 | if (cpumask_test_cpu(cpu, tracing_cpumask) && |
1985 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
1986 | atomic_inc(&global_trace.data[cpu]->disabled); |
1987 | } | |
9e01c1b7 RR |
1988 | if (!cpumask_test_cpu(cpu, tracing_cpumask) && |
1989 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { | |
36dfe925 IM |
1990 | atomic_dec(&global_trace.data[cpu]->disabled); |
1991 | } | |
1992 | } | |
92205c23 | 1993 | __raw_spin_unlock(&ftrace_max_lock); |
a5e25883 | 1994 | local_irq_enable(); |
36dfe925 | 1995 | |
9e01c1b7 | 1996 | cpumask_copy(tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
1997 | |
1998 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 1999 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
2000 | |
2001 | return count; | |
36dfe925 IM |
2002 | |
2003 | err_unlock: | |
2004 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 2005 | free_cpumask_var(tracing_cpumask); |
36dfe925 IM |
2006 | |
2007 | return err; | |
c7078de1 IM |
2008 | } |
2009 | ||
2010 | static struct file_operations tracing_cpumask_fops = { | |
2011 | .open = tracing_open_generic, | |
2012 | .read = tracing_cpumask_read, | |
2013 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2014 | }; |
2015 | ||
2016 | static ssize_t | |
ee6bce52 | 2017 | tracing_trace_options_read(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
2018 | size_t cnt, loff_t *ppos) |
2019 | { | |
d8e83d26 SR |
2020 | struct tracer_opt *trace_opts; |
2021 | u32 tracer_flags; | |
2022 | int len = 0; | |
bc0c38d1 SR |
2023 | char *buf; |
2024 | int r = 0; | |
d8e83d26 | 2025 | int i; |
adf9f195 | 2026 | |
bc0c38d1 | 2027 | |
c3706f00 | 2028 | /* calculate max size */ |
bc0c38d1 SR |
2029 | for (i = 0; trace_options[i]; i++) { |
2030 | len += strlen(trace_options[i]); | |
5c6a3ae1 | 2031 | len += 3; /* "no" and newline */ |
bc0c38d1 SR |
2032 | } |
2033 | ||
d8e83d26 SR |
2034 | mutex_lock(&trace_types_lock); |
2035 | tracer_flags = current_trace->flags->val; | |
2036 | trace_opts = current_trace->flags->opts; | |
2037 | ||
adf9f195 FW |
2038 | /* |
2039 | * Increase the size with names of options specific | |
2040 | * of the current tracer. | |
2041 | */ | |
2042 | for (i = 0; trace_opts[i].name; i++) { | |
2043 | len += strlen(trace_opts[i].name); | |
5c6a3ae1 | 2044 | len += 3; /* "no" and newline */ |
adf9f195 FW |
2045 | } |
2046 | ||
bc0c38d1 SR |
2047 | /* +2 for \n and \0 */ |
2048 | buf = kmalloc(len + 2, GFP_KERNEL); | |
d8e83d26 SR |
2049 | if (!buf) { |
2050 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 2051 | return -ENOMEM; |
d8e83d26 | 2052 | } |
bc0c38d1 SR |
2053 | |
2054 | for (i = 0; trace_options[i]; i++) { | |
2055 | if (trace_flags & (1 << i)) | |
5c6a3ae1 | 2056 | r += sprintf(buf + r, "%s\n", trace_options[i]); |
bc0c38d1 | 2057 | else |
5c6a3ae1 | 2058 | r += sprintf(buf + r, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
2059 | } |
2060 | ||
adf9f195 FW |
2061 | for (i = 0; trace_opts[i].name; i++) { |
2062 | if (tracer_flags & trace_opts[i].bit) | |
5c6a3ae1 | 2063 | r += sprintf(buf + r, "%s\n", |
adf9f195 FW |
2064 | trace_opts[i].name); |
2065 | else | |
5c6a3ae1 | 2066 | r += sprintf(buf + r, "no%s\n", |
adf9f195 FW |
2067 | trace_opts[i].name); |
2068 | } | |
d8e83d26 | 2069 | mutex_unlock(&trace_types_lock); |
adf9f195 | 2070 | |
bc0c38d1 SR |
2071 | WARN_ON(r >= len + 2); |
2072 | ||
36dfe925 | 2073 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2074 | |
2075 | kfree(buf); | |
bc0c38d1 SR |
2076 | return r; |
2077 | } | |
2078 | ||
adf9f195 FW |
2079 | /* Try to assign a tracer specific option */ |
2080 | static int set_tracer_option(struct tracer *trace, char *cmp, int neg) | |
2081 | { | |
2082 | struct tracer_flags *trace_flags = trace->flags; | |
2083 | struct tracer_opt *opts = NULL; | |
2084 | int ret = 0, i = 0; | |
2085 | int len; | |
2086 | ||
2087 | for (i = 0; trace_flags->opts[i].name; i++) { | |
2088 | opts = &trace_flags->opts[i]; | |
2089 | len = strlen(opts->name); | |
2090 | ||
2091 | if (strncmp(cmp, opts->name, len) == 0) { | |
2092 | ret = trace->set_flag(trace_flags->val, | |
2093 | opts->bit, !neg); | |
2094 | break; | |
2095 | } | |
2096 | } | |
2097 | /* Not found */ | |
2098 | if (!trace_flags->opts[i].name) | |
2099 | return -EINVAL; | |
2100 | ||
2101 | /* Refused to handle */ | |
2102 | if (ret) | |
2103 | return ret; | |
2104 | ||
2105 | if (neg) | |
2106 | trace_flags->val &= ~opts->bit; | |
2107 | else | |
2108 | trace_flags->val |= opts->bit; | |
2109 | ||
2110 | return 0; | |
2111 | } | |
2112 | ||
bc0c38d1 | 2113 | static ssize_t |
ee6bce52 | 2114 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, |
bc0c38d1 SR |
2115 | size_t cnt, loff_t *ppos) |
2116 | { | |
2117 | char buf[64]; | |
2118 | char *cmp = buf; | |
2119 | int neg = 0; | |
adf9f195 | 2120 | int ret; |
bc0c38d1 SR |
2121 | int i; |
2122 | ||
cffae437 SR |
2123 | if (cnt >= sizeof(buf)) |
2124 | return -EINVAL; | |
bc0c38d1 SR |
2125 | |
2126 | if (copy_from_user(&buf, ubuf, cnt)) | |
2127 | return -EFAULT; | |
2128 | ||
2129 | buf[cnt] = 0; | |
2130 | ||
2131 | if (strncmp(buf, "no", 2) == 0) { | |
2132 | neg = 1; | |
2133 | cmp += 2; | |
2134 | } | |
2135 | ||
2136 | for (i = 0; trace_options[i]; i++) { | |
2137 | int len = strlen(trace_options[i]); | |
2138 | ||
2139 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
2140 | if (neg) | |
2141 | trace_flags &= ~(1 << i); | |
2142 | else | |
2143 | trace_flags |= (1 << i); | |
2144 | break; | |
2145 | } | |
2146 | } | |
adf9f195 FW |
2147 | |
2148 | /* If no option could be set, test the specific tracer options */ | |
2149 | if (!trace_options[i]) { | |
d8e83d26 | 2150 | mutex_lock(&trace_types_lock); |
adf9f195 | 2151 | ret = set_tracer_option(current_trace, cmp, neg); |
d8e83d26 | 2152 | mutex_unlock(&trace_types_lock); |
adf9f195 FW |
2153 | if (ret) |
2154 | return ret; | |
2155 | } | |
bc0c38d1 SR |
2156 | |
2157 | filp->f_pos += cnt; | |
2158 | ||
2159 | return cnt; | |
2160 | } | |
2161 | ||
2162 | static struct file_operations tracing_iter_fops = { | |
c7078de1 | 2163 | .open = tracing_open_generic, |
ee6bce52 SR |
2164 | .read = tracing_trace_options_read, |
2165 | .write = tracing_trace_options_write, | |
bc0c38d1 SR |
2166 | }; |
2167 | ||
7bd2f24c IM |
2168 | static const char readme_msg[] = |
2169 | "tracing mini-HOWTO:\n\n" | |
2170 | "# mkdir /debug\n" | |
2171 | "# mount -t debugfs nodev /debug\n\n" | |
2172 | "# cat /debug/tracing/available_tracers\n" | |
2173 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
2174 | "# cat /debug/tracing/current_tracer\n" | |
2175 | "none\n" | |
2176 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
2177 | "# cat /debug/tracing/current_tracer\n" | |
2178 | "sched_switch\n" | |
ee6bce52 | 2179 | "# cat /debug/tracing/trace_options\n" |
7bd2f24c | 2180 | "noprint-parent nosym-offset nosym-addr noverbose\n" |
ee6bce52 | 2181 | "# echo print-parent > /debug/tracing/trace_options\n" |
7bd2f24c IM |
2182 | "# echo 1 > /debug/tracing/tracing_enabled\n" |
2183 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2184 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2185 | ; | |
2186 | ||
2187 | static ssize_t | |
2188 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2189 | size_t cnt, loff_t *ppos) | |
2190 | { | |
2191 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2192 | readme_msg, strlen(readme_msg)); | |
2193 | } | |
2194 | ||
2195 | static struct file_operations tracing_readme_fops = { | |
c7078de1 IM |
2196 | .open = tracing_open_generic, |
2197 | .read = tracing_readme_read, | |
7bd2f24c IM |
2198 | }; |
2199 | ||
bc0c38d1 SR |
2200 | static ssize_t |
2201 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2202 | size_t cnt, loff_t *ppos) | |
2203 | { | |
bc0c38d1 SR |
2204 | char buf[64]; |
2205 | int r; | |
2206 | ||
9036990d | 2207 | r = sprintf(buf, "%u\n", tracer_enabled); |
4e3c3333 | 2208 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2209 | } |
2210 | ||
2211 | static ssize_t | |
2212 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2213 | size_t cnt, loff_t *ppos) | |
2214 | { | |
2215 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2216 | char buf[64]; |
5e39841c | 2217 | unsigned long val; |
c6caeeb1 | 2218 | int ret; |
bc0c38d1 | 2219 | |
cffae437 SR |
2220 | if (cnt >= sizeof(buf)) |
2221 | return -EINVAL; | |
bc0c38d1 SR |
2222 | |
2223 | if (copy_from_user(&buf, ubuf, cnt)) | |
2224 | return -EFAULT; | |
2225 | ||
2226 | buf[cnt] = 0; | |
2227 | ||
c6caeeb1 SR |
2228 | ret = strict_strtoul(buf, 10, &val); |
2229 | if (ret < 0) | |
2230 | return ret; | |
bc0c38d1 SR |
2231 | |
2232 | val = !!val; | |
2233 | ||
2234 | mutex_lock(&trace_types_lock); | |
9036990d SR |
2235 | if (tracer_enabled ^ val) { |
2236 | if (val) { | |
bc0c38d1 | 2237 | tracer_enabled = 1; |
9036990d SR |
2238 | if (current_trace->start) |
2239 | current_trace->start(tr); | |
2240 | tracing_start(); | |
2241 | } else { | |
bc0c38d1 | 2242 | tracer_enabled = 0; |
9036990d SR |
2243 | tracing_stop(); |
2244 | if (current_trace->stop) | |
2245 | current_trace->stop(tr); | |
2246 | } | |
bc0c38d1 SR |
2247 | } |
2248 | mutex_unlock(&trace_types_lock); | |
2249 | ||
2250 | filp->f_pos += cnt; | |
2251 | ||
2252 | return cnt; | |
2253 | } | |
2254 | ||
2255 | static ssize_t | |
2256 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2257 | size_t cnt, loff_t *ppos) | |
2258 | { | |
2259 | char buf[max_tracer_type_len+2]; | |
2260 | int r; | |
2261 | ||
2262 | mutex_lock(&trace_types_lock); | |
2263 | if (current_trace) | |
2264 | r = sprintf(buf, "%s\n", current_trace->name); | |
2265 | else | |
2266 | r = sprintf(buf, "\n"); | |
2267 | mutex_unlock(&trace_types_lock); | |
2268 | ||
4bf39a94 | 2269 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2270 | } |
2271 | ||
b6f11df2 ACM |
2272 | int tracer_init(struct tracer *t, struct trace_array *tr) |
2273 | { | |
2274 | tracing_reset_online_cpus(tr); | |
2275 | return t->init(tr); | |
2276 | } | |
2277 | ||
577b785f SR |
2278 | struct trace_option_dentry; |
2279 | ||
2280 | static struct trace_option_dentry * | |
2281 | create_trace_option_files(struct tracer *tracer); | |
2282 | ||
2283 | static void | |
2284 | destroy_trace_option_files(struct trace_option_dentry *topts); | |
2285 | ||
b2821ae6 | 2286 | static int tracing_set_tracer(const char *buf) |
bc0c38d1 | 2287 | { |
577b785f | 2288 | static struct trace_option_dentry *topts; |
bc0c38d1 SR |
2289 | struct trace_array *tr = &global_trace; |
2290 | struct tracer *t; | |
d9e54076 | 2291 | int ret = 0; |
bc0c38d1 SR |
2292 | |
2293 | mutex_lock(&trace_types_lock); | |
2294 | for (t = trace_types; t; t = t->next) { | |
2295 | if (strcmp(t->name, buf) == 0) | |
2296 | break; | |
2297 | } | |
c2931e05 FW |
2298 | if (!t) { |
2299 | ret = -EINVAL; | |
2300 | goto out; | |
2301 | } | |
2302 | if (t == current_trace) | |
bc0c38d1 SR |
2303 | goto out; |
2304 | ||
9f029e83 | 2305 | trace_branch_disable(); |
bc0c38d1 SR |
2306 | if (current_trace && current_trace->reset) |
2307 | current_trace->reset(tr); | |
2308 | ||
577b785f SR |
2309 | destroy_trace_option_files(topts); |
2310 | ||
bc0c38d1 | 2311 | current_trace = t; |
577b785f SR |
2312 | |
2313 | topts = create_trace_option_files(current_trace); | |
2314 | ||
1c80025a | 2315 | if (t->init) { |
b6f11df2 | 2316 | ret = tracer_init(t, tr); |
1c80025a FW |
2317 | if (ret) |
2318 | goto out; | |
2319 | } | |
bc0c38d1 | 2320 | |
9f029e83 | 2321 | trace_branch_enable(tr); |
bc0c38d1 SR |
2322 | out: |
2323 | mutex_unlock(&trace_types_lock); | |
2324 | ||
d9e54076 PZ |
2325 | return ret; |
2326 | } | |
2327 | ||
2328 | static ssize_t | |
2329 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2330 | size_t cnt, loff_t *ppos) | |
2331 | { | |
2332 | char buf[max_tracer_type_len+1]; | |
2333 | int i; | |
2334 | size_t ret; | |
e6e7a65a FW |
2335 | int err; |
2336 | ||
2337 | ret = cnt; | |
d9e54076 PZ |
2338 | |
2339 | if (cnt > max_tracer_type_len) | |
2340 | cnt = max_tracer_type_len; | |
2341 | ||
2342 | if (copy_from_user(&buf, ubuf, cnt)) | |
2343 | return -EFAULT; | |
2344 | ||
2345 | buf[cnt] = 0; | |
2346 | ||
2347 | /* strip ending whitespace. */ | |
2348 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2349 | buf[i] = 0; | |
2350 | ||
e6e7a65a FW |
2351 | err = tracing_set_tracer(buf); |
2352 | if (err) | |
2353 | return err; | |
d9e54076 | 2354 | |
e6e7a65a | 2355 | filp->f_pos += ret; |
bc0c38d1 | 2356 | |
c2931e05 | 2357 | return ret; |
bc0c38d1 SR |
2358 | } |
2359 | ||
2360 | static ssize_t | |
2361 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2362 | size_t cnt, loff_t *ppos) | |
2363 | { | |
2364 | unsigned long *ptr = filp->private_data; | |
2365 | char buf[64]; | |
2366 | int r; | |
2367 | ||
cffae437 | 2368 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2369 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2370 | if (r > sizeof(buf)) |
2371 | r = sizeof(buf); | |
4bf39a94 | 2372 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2373 | } |
2374 | ||
2375 | static ssize_t | |
2376 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2377 | size_t cnt, loff_t *ppos) | |
2378 | { | |
5e39841c | 2379 | unsigned long *ptr = filp->private_data; |
bc0c38d1 | 2380 | char buf[64]; |
5e39841c | 2381 | unsigned long val; |
c6caeeb1 | 2382 | int ret; |
bc0c38d1 | 2383 | |
cffae437 SR |
2384 | if (cnt >= sizeof(buf)) |
2385 | return -EINVAL; | |
bc0c38d1 SR |
2386 | |
2387 | if (copy_from_user(&buf, ubuf, cnt)) | |
2388 | return -EFAULT; | |
2389 | ||
2390 | buf[cnt] = 0; | |
2391 | ||
c6caeeb1 SR |
2392 | ret = strict_strtoul(buf, 10, &val); |
2393 | if (ret < 0) | |
2394 | return ret; | |
bc0c38d1 SR |
2395 | |
2396 | *ptr = val * 1000; | |
2397 | ||
2398 | return cnt; | |
2399 | } | |
2400 | ||
b3806b43 SR |
2401 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
2402 | { | |
b04cc6b1 | 2403 | long cpu_file = (long) inode->i_private; |
b3806b43 | 2404 | struct trace_iterator *iter; |
b04cc6b1 | 2405 | int ret = 0; |
b3806b43 SR |
2406 | |
2407 | if (tracing_disabled) | |
2408 | return -ENODEV; | |
2409 | ||
b04cc6b1 FW |
2410 | mutex_lock(&trace_types_lock); |
2411 | ||
2412 | /* We only allow one reader per cpu */ | |
2413 | if (cpu_file == TRACE_PIPE_ALL_CPU) { | |
2414 | if (!cpumask_empty(tracing_reader_cpumask)) { | |
2415 | ret = -EBUSY; | |
2416 | goto out; | |
2417 | } | |
2418 | cpumask_setall(tracing_reader_cpumask); | |
2419 | } else { | |
2420 | if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask)) | |
2421 | cpumask_set_cpu(cpu_file, tracing_reader_cpumask); | |
2422 | else { | |
2423 | ret = -EBUSY; | |
2424 | goto out; | |
2425 | } | |
b3806b43 SR |
2426 | } |
2427 | ||
2428 | /* create a buffer to store the information to pass to userspace */ | |
2429 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
2430 | if (!iter) { |
2431 | ret = -ENOMEM; | |
2432 | goto out; | |
2433 | } | |
b3806b43 | 2434 | |
d7350c3f FW |
2435 | /* |
2436 | * We make a copy of the current tracer to avoid concurrent | |
2437 | * changes on it while we are reading. | |
2438 | */ | |
2439 | iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL); | |
2440 | if (!iter->trace) { | |
2441 | ret = -ENOMEM; | |
2442 | goto fail; | |
2443 | } | |
2444 | if (current_trace) | |
2445 | *iter->trace = *current_trace; | |
2446 | ||
4462344e | 2447 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 2448 | ret = -ENOMEM; |
d7350c3f | 2449 | goto fail; |
4462344e RR |
2450 | } |
2451 | ||
a309720c | 2452 | /* trace pipe does not show start of buffer */ |
4462344e | 2453 | cpumask_setall(iter->started); |
a309720c | 2454 | |
b04cc6b1 | 2455 | iter->cpu_file = cpu_file; |
b3806b43 | 2456 | iter->tr = &global_trace; |
d7350c3f | 2457 | mutex_init(&iter->mutex); |
b3806b43 SR |
2458 | filp->private_data = iter; |
2459 | ||
107bad8b SR |
2460 | if (iter->trace->pipe_open) |
2461 | iter->trace->pipe_open(iter); | |
107bad8b | 2462 | |
b04cc6b1 FW |
2463 | out: |
2464 | mutex_unlock(&trace_types_lock); | |
2465 | return ret; | |
d7350c3f FW |
2466 | |
2467 | fail: | |
2468 | kfree(iter->trace); | |
2469 | kfree(iter); | |
2470 | mutex_unlock(&trace_types_lock); | |
2471 | return ret; | |
b3806b43 SR |
2472 | } |
2473 | ||
2474 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2475 | { | |
2476 | struct trace_iterator *iter = file->private_data; | |
2477 | ||
b04cc6b1 FW |
2478 | mutex_lock(&trace_types_lock); |
2479 | ||
2480 | if (iter->cpu_file == TRACE_PIPE_ALL_CPU) | |
2481 | cpumask_clear(tracing_reader_cpumask); | |
2482 | else | |
2483 | cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask); | |
2484 | ||
2485 | mutex_unlock(&trace_types_lock); | |
2486 | ||
4462344e | 2487 | free_cpumask_var(iter->started); |
d7350c3f FW |
2488 | mutex_destroy(&iter->mutex); |
2489 | kfree(iter->trace); | |
b3806b43 | 2490 | kfree(iter); |
b3806b43 SR |
2491 | |
2492 | return 0; | |
2493 | } | |
2494 | ||
2a2cc8f7 SSP |
2495 | static unsigned int |
2496 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2497 | { | |
2498 | struct trace_iterator *iter = filp->private_data; | |
2499 | ||
2500 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2501 | /* | |
2502 | * Always select as readable when in blocking mode | |
2503 | */ | |
2504 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2505 | } else { |
2a2cc8f7 SSP |
2506 | if (!trace_empty(iter)) |
2507 | return POLLIN | POLLRDNORM; | |
2508 | poll_wait(filp, &trace_wait, poll_table); | |
2509 | if (!trace_empty(iter)) | |
2510 | return POLLIN | POLLRDNORM; | |
2511 | ||
2512 | return 0; | |
2513 | } | |
2514 | } | |
2515 | ||
6eaaa5d5 FW |
2516 | |
2517 | void default_wait_pipe(struct trace_iterator *iter) | |
2518 | { | |
2519 | DEFINE_WAIT(wait); | |
2520 | ||
2521 | prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE); | |
2522 | ||
2523 | if (trace_empty(iter)) | |
2524 | schedule(); | |
2525 | ||
2526 | finish_wait(&trace_wait, &wait); | |
2527 | } | |
2528 | ||
2529 | /* | |
2530 | * This is a make-shift waitqueue. | |
2531 | * A tracer might use this callback on some rare cases: | |
2532 | * | |
2533 | * 1) the current tracer might hold the runqueue lock when it wakes up | |
2534 | * a reader, hence a deadlock (sched, function, and function graph tracers) | |
2535 | * 2) the function tracers, trace all functions, we don't want | |
2536 | * the overhead of calling wake_up and friends | |
2537 | * (and tracing them too) | |
2538 | * | |
2539 | * Anyway, this is really very primitive wakeup. | |
2540 | */ | |
2541 | void poll_wait_pipe(struct trace_iterator *iter) | |
2542 | { | |
2543 | set_current_state(TASK_INTERRUPTIBLE); | |
2544 | /* sleep for 100 msecs, and try again. */ | |
2545 | schedule_timeout(HZ / 10); | |
2546 | } | |
2547 | ||
ff98781b EGM |
2548 | /* Must be called with trace_types_lock mutex held. */ |
2549 | static int tracing_wait_pipe(struct file *filp) | |
b3806b43 SR |
2550 | { |
2551 | struct trace_iterator *iter = filp->private_data; | |
b3806b43 | 2552 | |
b3806b43 | 2553 | while (trace_empty(iter)) { |
2dc8f095 | 2554 | |
107bad8b | 2555 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 2556 | return -EAGAIN; |
107bad8b | 2557 | } |
2dc8f095 | 2558 | |
d7350c3f | 2559 | mutex_unlock(&iter->mutex); |
107bad8b | 2560 | |
6eaaa5d5 | 2561 | iter->trace->wait_pipe(iter); |
b3806b43 | 2562 | |
d7350c3f | 2563 | mutex_lock(&iter->mutex); |
107bad8b | 2564 | |
6eaaa5d5 | 2565 | if (signal_pending(current)) |
ff98781b | 2566 | return -EINTR; |
b3806b43 SR |
2567 | |
2568 | /* | |
2569 | * We block until we read something and tracing is disabled. | |
2570 | * We still block if tracing is disabled, but we have never | |
2571 | * read anything. This allows a user to cat this file, and | |
2572 | * then enable tracing. But after we have read something, | |
2573 | * we give an EOF when tracing is again disabled. | |
2574 | * | |
2575 | * iter->pos will be 0 if we haven't read anything. | |
2576 | */ | |
2577 | if (!tracer_enabled && iter->pos) | |
2578 | break; | |
b3806b43 SR |
2579 | } |
2580 | ||
ff98781b EGM |
2581 | return 1; |
2582 | } | |
2583 | ||
2584 | /* | |
2585 | * Consumer reader. | |
2586 | */ | |
2587 | static ssize_t | |
2588 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2589 | size_t cnt, loff_t *ppos) | |
2590 | { | |
2591 | struct trace_iterator *iter = filp->private_data; | |
d7350c3f | 2592 | static struct tracer *old_tracer; |
ff98781b EGM |
2593 | ssize_t sret; |
2594 | ||
2595 | /* return any leftover data */ | |
2596 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
2597 | if (sret != -EBUSY) | |
2598 | return sret; | |
2599 | ||
f9520750 | 2600 | trace_seq_init(&iter->seq); |
ff98781b | 2601 | |
d7350c3f | 2602 | /* copy the tracer to avoid using a global lock all around */ |
ff98781b | 2603 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2604 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2605 | old_tracer = current_trace; | |
2606 | *iter->trace = *current_trace; | |
2607 | } | |
2608 | mutex_unlock(&trace_types_lock); | |
2609 | ||
2610 | /* | |
2611 | * Avoid more than one consumer on a single file descriptor | |
2612 | * This is just a matter of traces coherency, the ring buffer itself | |
2613 | * is protected. | |
2614 | */ | |
2615 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
2616 | if (iter->trace->read) { |
2617 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
2618 | if (sret) | |
2619 | goto out; | |
2620 | } | |
2621 | ||
2622 | waitagain: | |
2623 | sret = tracing_wait_pipe(filp); | |
2624 | if (sret <= 0) | |
2625 | goto out; | |
2626 | ||
b3806b43 | 2627 | /* stop when tracing is finished */ |
ff98781b EGM |
2628 | if (trace_empty(iter)) { |
2629 | sret = 0; | |
107bad8b | 2630 | goto out; |
ff98781b | 2631 | } |
b3806b43 SR |
2632 | |
2633 | if (cnt >= PAGE_SIZE) | |
2634 | cnt = PAGE_SIZE - 1; | |
2635 | ||
53d0aa77 | 2636 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2637 | memset(&iter->seq, 0, |
2638 | sizeof(struct trace_iterator) - | |
2639 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2640 | iter->pos = -1; |
b3806b43 | 2641 | |
088b1e42 | 2642 | while (find_next_entry_inc(iter) != NULL) { |
2c4f035f | 2643 | enum print_line_t ret; |
088b1e42 SR |
2644 | int len = iter->seq.len; |
2645 | ||
f9896bf3 | 2646 | ret = print_trace_line(iter); |
2c4f035f | 2647 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 SR |
2648 | /* don't print partial lines */ |
2649 | iter->seq.len = len; | |
b3806b43 | 2650 | break; |
088b1e42 | 2651 | } |
b91facc3 FW |
2652 | if (ret != TRACE_TYPE_NO_CONSUME) |
2653 | trace_consume(iter); | |
b3806b43 SR |
2654 | |
2655 | if (iter->seq.len >= cnt) | |
2656 | break; | |
b3806b43 SR |
2657 | } |
2658 | ||
b3806b43 | 2659 | /* Now copy what we have to the user */ |
6c6c2796 PP |
2660 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2661 | if (iter->seq.readpos >= iter->seq.len) | |
f9520750 | 2662 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
2663 | |
2664 | /* | |
2665 | * If there was nothing to send to user, inspite of consuming trace | |
2666 | * entries, go back to wait for more entries. | |
2667 | */ | |
6c6c2796 | 2668 | if (sret == -EBUSY) |
9ff4b974 | 2669 | goto waitagain; |
b3806b43 | 2670 | |
107bad8b | 2671 | out: |
d7350c3f | 2672 | mutex_unlock(&iter->mutex); |
107bad8b | 2673 | |
6c6c2796 | 2674 | return sret; |
b3806b43 SR |
2675 | } |
2676 | ||
3c56819b EGM |
2677 | static void tracing_pipe_buf_release(struct pipe_inode_info *pipe, |
2678 | struct pipe_buffer *buf) | |
2679 | { | |
2680 | __free_page(buf->page); | |
2681 | } | |
2682 | ||
2683 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, | |
2684 | unsigned int idx) | |
2685 | { | |
2686 | __free_page(spd->pages[idx]); | |
2687 | } | |
2688 | ||
2689 | static struct pipe_buf_operations tracing_pipe_buf_ops = { | |
34cd4998 SR |
2690 | .can_merge = 0, |
2691 | .map = generic_pipe_buf_map, | |
2692 | .unmap = generic_pipe_buf_unmap, | |
2693 | .confirm = generic_pipe_buf_confirm, | |
2694 | .release = tracing_pipe_buf_release, | |
2695 | .steal = generic_pipe_buf_steal, | |
2696 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
2697 | }; |
2698 | ||
34cd4998 | 2699 | static size_t |
fa7c7f6e | 2700 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
2701 | { |
2702 | size_t count; | |
2703 | int ret; | |
2704 | ||
2705 | /* Seq buffer is page-sized, exactly what we need. */ | |
2706 | for (;;) { | |
2707 | count = iter->seq.len; | |
2708 | ret = print_trace_line(iter); | |
2709 | count = iter->seq.len - count; | |
2710 | if (rem < count) { | |
2711 | rem = 0; | |
2712 | iter->seq.len -= count; | |
2713 | break; | |
2714 | } | |
2715 | if (ret == TRACE_TYPE_PARTIAL_LINE) { | |
2716 | iter->seq.len -= count; | |
2717 | break; | |
2718 | } | |
2719 | ||
2720 | trace_consume(iter); | |
2721 | rem -= count; | |
2722 | if (!find_next_entry_inc(iter)) { | |
2723 | rem = 0; | |
2724 | iter->ent = NULL; | |
2725 | break; | |
2726 | } | |
2727 | } | |
2728 | ||
2729 | return rem; | |
2730 | } | |
2731 | ||
3c56819b EGM |
2732 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
2733 | loff_t *ppos, | |
2734 | struct pipe_inode_info *pipe, | |
2735 | size_t len, | |
2736 | unsigned int flags) | |
2737 | { | |
2738 | struct page *pages[PIPE_BUFFERS]; | |
2739 | struct partial_page partial[PIPE_BUFFERS]; | |
2740 | struct trace_iterator *iter = filp->private_data; | |
2741 | struct splice_pipe_desc spd = { | |
34cd4998 SR |
2742 | .pages = pages, |
2743 | .partial = partial, | |
2744 | .nr_pages = 0, /* This gets updated below. */ | |
2745 | .flags = flags, | |
2746 | .ops = &tracing_pipe_buf_ops, | |
2747 | .spd_release = tracing_spd_release_pipe, | |
3c56819b | 2748 | }; |
d7350c3f | 2749 | static struct tracer *old_tracer; |
3c56819b | 2750 | ssize_t ret; |
34cd4998 | 2751 | size_t rem; |
3c56819b EGM |
2752 | unsigned int i; |
2753 | ||
d7350c3f | 2754 | /* copy the tracer to avoid using a global lock all around */ |
3c56819b | 2755 | mutex_lock(&trace_types_lock); |
d7350c3f FW |
2756 | if (unlikely(old_tracer != current_trace && current_trace)) { |
2757 | old_tracer = current_trace; | |
2758 | *iter->trace = *current_trace; | |
2759 | } | |
2760 | mutex_unlock(&trace_types_lock); | |
2761 | ||
2762 | mutex_lock(&iter->mutex); | |
3c56819b EGM |
2763 | |
2764 | if (iter->trace->splice_read) { | |
2765 | ret = iter->trace->splice_read(iter, filp, | |
2766 | ppos, pipe, len, flags); | |
2767 | if (ret) | |
34cd4998 | 2768 | goto out_err; |
3c56819b EGM |
2769 | } |
2770 | ||
2771 | ret = tracing_wait_pipe(filp); | |
2772 | if (ret <= 0) | |
34cd4998 | 2773 | goto out_err; |
3c56819b EGM |
2774 | |
2775 | if (!iter->ent && !find_next_entry_inc(iter)) { | |
2776 | ret = -EFAULT; | |
34cd4998 | 2777 | goto out_err; |
3c56819b EGM |
2778 | } |
2779 | ||
2780 | /* Fill as many pages as possible. */ | |
2781 | for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) { | |
2782 | pages[i] = alloc_page(GFP_KERNEL); | |
34cd4998 SR |
2783 | if (!pages[i]) |
2784 | break; | |
3c56819b | 2785 | |
fa7c7f6e | 2786 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
2787 | |
2788 | /* Copy the data into the page, so we can start over. */ | |
2789 | ret = trace_seq_to_buffer(&iter->seq, | |
2790 | page_address(pages[i]), | |
2791 | iter->seq.len); | |
2792 | if (ret < 0) { | |
2793 | __free_page(pages[i]); | |
2794 | break; | |
2795 | } | |
2796 | partial[i].offset = 0; | |
2797 | partial[i].len = iter->seq.len; | |
2798 | ||
f9520750 | 2799 | trace_seq_init(&iter->seq); |
3c56819b EGM |
2800 | } |
2801 | ||
d7350c3f | 2802 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
2803 | |
2804 | spd.nr_pages = i; | |
2805 | ||
2806 | return splice_to_pipe(pipe, &spd); | |
2807 | ||
34cd4998 | 2808 | out_err: |
d7350c3f | 2809 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
2810 | |
2811 | return ret; | |
2812 | } | |
2813 | ||
a98a3c3f SR |
2814 | static ssize_t |
2815 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
2816 | size_t cnt, loff_t *ppos) | |
2817 | { | |
2818 | struct trace_array *tr = filp->private_data; | |
2819 | char buf[64]; | |
2820 | int r; | |
2821 | ||
1696b2b0 | 2822 | r = sprintf(buf, "%lu\n", tr->entries >> 10); |
a98a3c3f SR |
2823 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
2824 | } | |
2825 | ||
2826 | static ssize_t | |
2827 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
2828 | size_t cnt, loff_t *ppos) | |
2829 | { | |
2830 | unsigned long val; | |
2831 | char buf[64]; | |
bf5e6519 | 2832 | int ret, cpu; |
a98a3c3f | 2833 | |
cffae437 SR |
2834 | if (cnt >= sizeof(buf)) |
2835 | return -EINVAL; | |
a98a3c3f SR |
2836 | |
2837 | if (copy_from_user(&buf, ubuf, cnt)) | |
2838 | return -EFAULT; | |
2839 | ||
2840 | buf[cnt] = 0; | |
2841 | ||
c6caeeb1 SR |
2842 | ret = strict_strtoul(buf, 10, &val); |
2843 | if (ret < 0) | |
2844 | return ret; | |
a98a3c3f SR |
2845 | |
2846 | /* must have at least 1 entry */ | |
2847 | if (!val) | |
2848 | return -EINVAL; | |
2849 | ||
2850 | mutex_lock(&trace_types_lock); | |
2851 | ||
c76f0694 | 2852 | tracing_stop(); |
a98a3c3f | 2853 | |
bf5e6519 SR |
2854 | /* disable all cpu buffers */ |
2855 | for_each_tracing_cpu(cpu) { | |
2856 | if (global_trace.data[cpu]) | |
2857 | atomic_inc(&global_trace.data[cpu]->disabled); | |
2858 | if (max_tr.data[cpu]) | |
2859 | atomic_inc(&max_tr.data[cpu]->disabled); | |
2860 | } | |
2861 | ||
1696b2b0 SR |
2862 | /* value is in KB */ |
2863 | val <<= 10; | |
2864 | ||
3928a8a2 SR |
2865 | if (val != global_trace.entries) { |
2866 | ret = ring_buffer_resize(global_trace.buffer, val); | |
2867 | if (ret < 0) { | |
2868 | cnt = ret; | |
3eefae99 SR |
2869 | goto out; |
2870 | } | |
2871 | ||
3928a8a2 SR |
2872 | ret = ring_buffer_resize(max_tr.buffer, val); |
2873 | if (ret < 0) { | |
2874 | int r; | |
2875 | cnt = ret; | |
2876 | r = ring_buffer_resize(global_trace.buffer, | |
2877 | global_trace.entries); | |
2878 | if (r < 0) { | |
2879 | /* AARGH! We are left with different | |
2880 | * size max buffer!!!! */ | |
2881 | WARN_ON(1); | |
2882 | tracing_disabled = 1; | |
a98a3c3f | 2883 | } |
3928a8a2 | 2884 | goto out; |
a98a3c3f | 2885 | } |
3eefae99 | 2886 | |
3928a8a2 | 2887 | global_trace.entries = val; |
a98a3c3f SR |
2888 | } |
2889 | ||
2890 | filp->f_pos += cnt; | |
2891 | ||
19384c03 SR |
2892 | /* If check pages failed, return ENOMEM */ |
2893 | if (tracing_disabled) | |
2894 | cnt = -ENOMEM; | |
a98a3c3f | 2895 | out: |
bf5e6519 SR |
2896 | for_each_tracing_cpu(cpu) { |
2897 | if (global_trace.data[cpu]) | |
2898 | atomic_dec(&global_trace.data[cpu]->disabled); | |
2899 | if (max_tr.data[cpu]) | |
2900 | atomic_dec(&max_tr.data[cpu]->disabled); | |
2901 | } | |
2902 | ||
c76f0694 | 2903 | tracing_start(); |
a98a3c3f SR |
2904 | max_tr.entries = global_trace.entries; |
2905 | mutex_unlock(&trace_types_lock); | |
2906 | ||
2907 | return cnt; | |
2908 | } | |
2909 | ||
5bf9a1ee PP |
2910 | static int mark_printk(const char *fmt, ...) |
2911 | { | |
2912 | int ret; | |
2913 | va_list args; | |
2914 | va_start(args, fmt); | |
1fd8f2a3 | 2915 | ret = trace_vprintk(0, -1, fmt, args); |
5bf9a1ee PP |
2916 | va_end(args); |
2917 | return ret; | |
2918 | } | |
2919 | ||
2920 | static ssize_t | |
2921 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
2922 | size_t cnt, loff_t *fpos) | |
2923 | { | |
2924 | char *buf; | |
2925 | char *end; | |
5bf9a1ee | 2926 | |
c76f0694 | 2927 | if (tracing_disabled) |
5bf9a1ee PP |
2928 | return -EINVAL; |
2929 | ||
2930 | if (cnt > TRACE_BUF_SIZE) | |
2931 | cnt = TRACE_BUF_SIZE; | |
2932 | ||
2933 | buf = kmalloc(cnt + 1, GFP_KERNEL); | |
2934 | if (buf == NULL) | |
2935 | return -ENOMEM; | |
2936 | ||
2937 | if (copy_from_user(buf, ubuf, cnt)) { | |
2938 | kfree(buf); | |
2939 | return -EFAULT; | |
2940 | } | |
2941 | ||
2942 | /* Cut from the first nil or newline. */ | |
2943 | buf[cnt] = '\0'; | |
2944 | end = strchr(buf, '\n'); | |
2945 | if (end) | |
2946 | *end = '\0'; | |
2947 | ||
2948 | cnt = mark_printk("%s\n", buf); | |
2949 | kfree(buf); | |
2950 | *fpos += cnt; | |
2951 | ||
2952 | return cnt; | |
2953 | } | |
2954 | ||
bc0c38d1 | 2955 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2956 | .open = tracing_open_generic, |
2957 | .read = tracing_max_lat_read, | |
2958 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2959 | }; |
2960 | ||
2961 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2962 | .open = tracing_open_generic, |
2963 | .read = tracing_ctrl_read, | |
2964 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2965 | }; |
2966 | ||
2967 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2968 | .open = tracing_open_generic, |
2969 | .read = tracing_set_trace_read, | |
2970 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2971 | }; |
2972 | ||
b3806b43 | 2973 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 | 2974 | .open = tracing_open_pipe, |
2a2cc8f7 | 2975 | .poll = tracing_poll_pipe, |
4bf39a94 | 2976 | .read = tracing_read_pipe, |
3c56819b | 2977 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 2978 | .release = tracing_release_pipe, |
b3806b43 SR |
2979 | }; |
2980 | ||
a98a3c3f SR |
2981 | static struct file_operations tracing_entries_fops = { |
2982 | .open = tracing_open_generic, | |
2983 | .read = tracing_entries_read, | |
2984 | .write = tracing_entries_write, | |
2985 | }; | |
2986 | ||
5bf9a1ee | 2987 | static struct file_operations tracing_mark_fops = { |
43a15386 | 2988 | .open = tracing_open_generic, |
5bf9a1ee PP |
2989 | .write = tracing_mark_write, |
2990 | }; | |
2991 | ||
2cadf913 SR |
2992 | struct ftrace_buffer_info { |
2993 | struct trace_array *tr; | |
2994 | void *spare; | |
2995 | int cpu; | |
2996 | unsigned int read; | |
2997 | }; | |
2998 | ||
2999 | static int tracing_buffers_open(struct inode *inode, struct file *filp) | |
3000 | { | |
3001 | int cpu = (int)(long)inode->i_private; | |
3002 | struct ftrace_buffer_info *info; | |
3003 | ||
3004 | if (tracing_disabled) | |
3005 | return -ENODEV; | |
3006 | ||
3007 | info = kzalloc(sizeof(*info), GFP_KERNEL); | |
3008 | if (!info) | |
3009 | return -ENOMEM; | |
3010 | ||
3011 | info->tr = &global_trace; | |
3012 | info->cpu = cpu; | |
3013 | info->spare = ring_buffer_alloc_read_page(info->tr->buffer); | |
3014 | /* Force reading ring buffer for first read */ | |
3015 | info->read = (unsigned int)-1; | |
3016 | if (!info->spare) | |
3017 | goto out; | |
3018 | ||
3019 | filp->private_data = info; | |
3020 | ||
3021 | return 0; | |
3022 | ||
3023 | out: | |
3024 | kfree(info); | |
3025 | return -ENOMEM; | |
3026 | } | |
3027 | ||
3028 | static ssize_t | |
3029 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
3030 | size_t count, loff_t *ppos) | |
3031 | { | |
3032 | struct ftrace_buffer_info *info = filp->private_data; | |
3033 | unsigned int pos; | |
3034 | ssize_t ret; | |
3035 | size_t size; | |
3036 | ||
2dc5d12b SR |
3037 | if (!count) |
3038 | return 0; | |
3039 | ||
2cadf913 SR |
3040 | /* Do we have previous read data to read? */ |
3041 | if (info->read < PAGE_SIZE) | |
3042 | goto read; | |
3043 | ||
3044 | info->read = 0; | |
3045 | ||
3046 | ret = ring_buffer_read_page(info->tr->buffer, | |
3047 | &info->spare, | |
3048 | count, | |
3049 | info->cpu, 0); | |
3050 | if (ret < 0) | |
3051 | return 0; | |
3052 | ||
3053 | pos = ring_buffer_page_len(info->spare); | |
3054 | ||
3055 | if (pos < PAGE_SIZE) | |
3056 | memset(info->spare + pos, 0, PAGE_SIZE - pos); | |
3057 | ||
3058 | read: | |
3059 | size = PAGE_SIZE - info->read; | |
3060 | if (size > count) | |
3061 | size = count; | |
3062 | ||
3063 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
2dc5d12b | 3064 | if (ret == size) |
2cadf913 | 3065 | return -EFAULT; |
2dc5d12b SR |
3066 | size -= ret; |
3067 | ||
2cadf913 SR |
3068 | *ppos += size; |
3069 | info->read += size; | |
3070 | ||
3071 | return size; | |
3072 | } | |
3073 | ||
3074 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
3075 | { | |
3076 | struct ftrace_buffer_info *info = file->private_data; | |
3077 | ||
3078 | ring_buffer_free_read_page(info->tr->buffer, info->spare); | |
3079 | kfree(info); | |
3080 | ||
3081 | return 0; | |
3082 | } | |
3083 | ||
3084 | struct buffer_ref { | |
3085 | struct ring_buffer *buffer; | |
3086 | void *page; | |
3087 | int ref; | |
3088 | }; | |
3089 | ||
3090 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
3091 | struct pipe_buffer *buf) | |
3092 | { | |
3093 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3094 | ||
3095 | if (--ref->ref) | |
3096 | return; | |
3097 | ||
3098 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3099 | kfree(ref); | |
3100 | buf->private = 0; | |
3101 | } | |
3102 | ||
3103 | static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe, | |
3104 | struct pipe_buffer *buf) | |
3105 | { | |
3106 | return 1; | |
3107 | } | |
3108 | ||
3109 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, | |
3110 | struct pipe_buffer *buf) | |
3111 | { | |
3112 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
3113 | ||
3114 | ref->ref++; | |
3115 | } | |
3116 | ||
3117 | /* Pipe buffer operations for a buffer. */ | |
3118 | static struct pipe_buf_operations buffer_pipe_buf_ops = { | |
3119 | .can_merge = 0, | |
3120 | .map = generic_pipe_buf_map, | |
3121 | .unmap = generic_pipe_buf_unmap, | |
3122 | .confirm = generic_pipe_buf_confirm, | |
3123 | .release = buffer_pipe_buf_release, | |
3124 | .steal = buffer_pipe_buf_steal, | |
3125 | .get = buffer_pipe_buf_get, | |
3126 | }; | |
3127 | ||
3128 | /* | |
3129 | * Callback from splice_to_pipe(), if we need to release some pages | |
3130 | * at the end of the spd in case we error'ed out in filling the pipe. | |
3131 | */ | |
3132 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
3133 | { | |
3134 | struct buffer_ref *ref = | |
3135 | (struct buffer_ref *)spd->partial[i].private; | |
3136 | ||
3137 | if (--ref->ref) | |
3138 | return; | |
3139 | ||
3140 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
3141 | kfree(ref); | |
3142 | spd->partial[i].private = 0; | |
3143 | } | |
3144 | ||
3145 | static ssize_t | |
3146 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
3147 | struct pipe_inode_info *pipe, size_t len, | |
3148 | unsigned int flags) | |
3149 | { | |
3150 | struct ftrace_buffer_info *info = file->private_data; | |
3151 | struct partial_page partial[PIPE_BUFFERS]; | |
3152 | struct page *pages[PIPE_BUFFERS]; | |
3153 | struct splice_pipe_desc spd = { | |
3154 | .pages = pages, | |
3155 | .partial = partial, | |
3156 | .flags = flags, | |
3157 | .ops = &buffer_pipe_buf_ops, | |
3158 | .spd_release = buffer_spd_release, | |
3159 | }; | |
3160 | struct buffer_ref *ref; | |
3161 | int size, i; | |
3162 | size_t ret; | |
3163 | ||
3164 | /* | |
3165 | * We can't seek on a buffer input | |
3166 | */ | |
3167 | if (unlikely(*ppos)) | |
3168 | return -ESPIPE; | |
3169 | ||
3170 | ||
3171 | for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) { | |
3172 | struct page *page; | |
3173 | int r; | |
3174 | ||
3175 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
3176 | if (!ref) | |
3177 | break; | |
3178 | ||
3179 | ref->buffer = info->tr->buffer; | |
3180 | ref->page = ring_buffer_alloc_read_page(ref->buffer); | |
3181 | if (!ref->page) { | |
3182 | kfree(ref); | |
3183 | break; | |
3184 | } | |
3185 | ||
3186 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
3187 | len, info->cpu, 0); | |
3188 | if (r < 0) { | |
3189 | ring_buffer_free_read_page(ref->buffer, | |
3190 | ref->page); | |
3191 | kfree(ref); | |
3192 | break; | |
3193 | } | |
3194 | ||
3195 | /* | |
3196 | * zero out any left over data, this is going to | |
3197 | * user land. | |
3198 | */ | |
3199 | size = ring_buffer_page_len(ref->page); | |
3200 | if (size < PAGE_SIZE) | |
3201 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
3202 | ||
3203 | page = virt_to_page(ref->page); | |
3204 | ||
3205 | spd.pages[i] = page; | |
3206 | spd.partial[i].len = PAGE_SIZE; | |
3207 | spd.partial[i].offset = 0; | |
3208 | spd.partial[i].private = (unsigned long)ref; | |
3209 | spd.nr_pages++; | |
3210 | } | |
3211 | ||
3212 | spd.nr_pages = i; | |
3213 | ||
3214 | /* did we read anything? */ | |
3215 | if (!spd.nr_pages) { | |
3216 | if (flags & SPLICE_F_NONBLOCK) | |
3217 | ret = -EAGAIN; | |
3218 | else | |
3219 | ret = 0; | |
3220 | /* TODO: block */ | |
3221 | return ret; | |
3222 | } | |
3223 | ||
3224 | ret = splice_to_pipe(pipe, &spd); | |
3225 | ||
3226 | return ret; | |
3227 | } | |
3228 | ||
3229 | static const struct file_operations tracing_buffers_fops = { | |
3230 | .open = tracing_buffers_open, | |
3231 | .read = tracing_buffers_read, | |
3232 | .release = tracing_buffers_release, | |
3233 | .splice_read = tracing_buffers_splice_read, | |
3234 | .llseek = no_llseek, | |
3235 | }; | |
3236 | ||
bc0c38d1 SR |
3237 | #ifdef CONFIG_DYNAMIC_FTRACE |
3238 | ||
b807c3d0 SR |
3239 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
3240 | { | |
3241 | return 0; | |
3242 | } | |
3243 | ||
bc0c38d1 | 3244 | static ssize_t |
b807c3d0 | 3245 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
3246 | size_t cnt, loff_t *ppos) |
3247 | { | |
a26a2a27 SR |
3248 | static char ftrace_dyn_info_buffer[1024]; |
3249 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 3250 | unsigned long *p = filp->private_data; |
b807c3d0 | 3251 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 3252 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
3253 | int r; |
3254 | ||
b807c3d0 SR |
3255 | mutex_lock(&dyn_info_mutex); |
3256 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 3257 | |
a26a2a27 | 3258 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
3259 | buf[r++] = '\n'; |
3260 | ||
3261 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
3262 | ||
3263 | mutex_unlock(&dyn_info_mutex); | |
3264 | ||
3265 | return r; | |
bc0c38d1 SR |
3266 | } |
3267 | ||
b807c3d0 | 3268 | static struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 3269 | .open = tracing_open_generic, |
b807c3d0 | 3270 | .read = tracing_read_dyn_info, |
bc0c38d1 SR |
3271 | }; |
3272 | #endif | |
3273 | ||
3274 | static struct dentry *d_tracer; | |
3275 | ||
3276 | struct dentry *tracing_init_dentry(void) | |
3277 | { | |
3278 | static int once; | |
3279 | ||
3280 | if (d_tracer) | |
3281 | return d_tracer; | |
3282 | ||
3283 | d_tracer = debugfs_create_dir("tracing", NULL); | |
3284 | ||
3285 | if (!d_tracer && !once) { | |
3286 | once = 1; | |
3287 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
3288 | return NULL; | |
3289 | } | |
3290 | ||
3291 | return d_tracer; | |
3292 | } | |
3293 | ||
b04cc6b1 FW |
3294 | static struct dentry *d_percpu; |
3295 | ||
3296 | struct dentry *tracing_dentry_percpu(void) | |
3297 | { | |
3298 | static int once; | |
3299 | struct dentry *d_tracer; | |
3300 | ||
3301 | if (d_percpu) | |
3302 | return d_percpu; | |
3303 | ||
3304 | d_tracer = tracing_init_dentry(); | |
3305 | ||
3306 | if (!d_tracer) | |
3307 | return NULL; | |
3308 | ||
3309 | d_percpu = debugfs_create_dir("per_cpu", d_tracer); | |
3310 | ||
3311 | if (!d_percpu && !once) { | |
3312 | once = 1; | |
3313 | pr_warning("Could not create debugfs directory 'per_cpu'\n"); | |
3314 | return NULL; | |
3315 | } | |
3316 | ||
3317 | return d_percpu; | |
3318 | } | |
3319 | ||
3320 | static void tracing_init_debugfs_percpu(long cpu) | |
3321 | { | |
3322 | struct dentry *d_percpu = tracing_dentry_percpu(); | |
8656e7a2 FW |
3323 | struct dentry *entry, *d_cpu; |
3324 | /* strlen(cpu) + MAX(log10(cpu)) + '\0' */ | |
3325 | char cpu_dir[7]; | |
b04cc6b1 FW |
3326 | |
3327 | if (cpu > 999 || cpu < 0) | |
3328 | return; | |
3329 | ||
8656e7a2 FW |
3330 | sprintf(cpu_dir, "cpu%ld", cpu); |
3331 | d_cpu = debugfs_create_dir(cpu_dir, d_percpu); | |
3332 | if (!d_cpu) { | |
3333 | pr_warning("Could not create debugfs '%s' entry\n", cpu_dir); | |
3334 | return; | |
3335 | } | |
b04cc6b1 | 3336 | |
8656e7a2 FW |
3337 | /* per cpu trace_pipe */ |
3338 | entry = debugfs_create_file("trace_pipe", 0444, d_cpu, | |
b04cc6b1 FW |
3339 | (void *) cpu, &tracing_pipe_fops); |
3340 | if (!entry) | |
8656e7a2 | 3341 | pr_warning("Could not create debugfs 'trace_pipe' entry\n"); |
b04cc6b1 FW |
3342 | |
3343 | /* per cpu trace */ | |
8656e7a2 | 3344 | entry = debugfs_create_file("trace", 0444, d_cpu, |
b04cc6b1 FW |
3345 | (void *) cpu, &tracing_fops); |
3346 | if (!entry) | |
8656e7a2 | 3347 | pr_warning("Could not create debugfs 'trace' entry\n"); |
b04cc6b1 FW |
3348 | } |
3349 | ||
60a11774 SR |
3350 | #ifdef CONFIG_FTRACE_SELFTEST |
3351 | /* Let selftest have access to static functions in this file */ | |
3352 | #include "trace_selftest.c" | |
3353 | #endif | |
3354 | ||
577b785f SR |
3355 | struct trace_option_dentry { |
3356 | struct tracer_opt *opt; | |
3357 | struct tracer_flags *flags; | |
3358 | struct dentry *entry; | |
3359 | }; | |
3360 | ||
3361 | static ssize_t | |
3362 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3363 | loff_t *ppos) | |
3364 | { | |
3365 | struct trace_option_dentry *topt = filp->private_data; | |
3366 | char *buf; | |
3367 | ||
3368 | if (topt->flags->val & topt->opt->bit) | |
3369 | buf = "1\n"; | |
3370 | else | |
3371 | buf = "0\n"; | |
3372 | ||
3373 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3374 | } | |
3375 | ||
3376 | static ssize_t | |
3377 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3378 | loff_t *ppos) | |
3379 | { | |
3380 | struct trace_option_dentry *topt = filp->private_data; | |
3381 | unsigned long val; | |
3382 | char buf[64]; | |
3383 | int ret; | |
3384 | ||
3385 | if (cnt >= sizeof(buf)) | |
3386 | return -EINVAL; | |
3387 | ||
3388 | if (copy_from_user(&buf, ubuf, cnt)) | |
3389 | return -EFAULT; | |
3390 | ||
3391 | buf[cnt] = 0; | |
3392 | ||
3393 | ret = strict_strtoul(buf, 10, &val); | |
3394 | if (ret < 0) | |
3395 | return ret; | |
3396 | ||
3397 | ret = 0; | |
3398 | switch (val) { | |
3399 | case 0: | |
3400 | /* do nothing if already cleared */ | |
3401 | if (!(topt->flags->val & topt->opt->bit)) | |
3402 | break; | |
3403 | ||
3404 | mutex_lock(&trace_types_lock); | |
3405 | if (current_trace->set_flag) | |
3406 | ret = current_trace->set_flag(topt->flags->val, | |
3407 | topt->opt->bit, 0); | |
3408 | mutex_unlock(&trace_types_lock); | |
3409 | if (ret) | |
3410 | return ret; | |
3411 | topt->flags->val &= ~topt->opt->bit; | |
3412 | break; | |
3413 | case 1: | |
3414 | /* do nothing if already set */ | |
3415 | if (topt->flags->val & topt->opt->bit) | |
3416 | break; | |
3417 | ||
3418 | mutex_lock(&trace_types_lock); | |
3419 | if (current_trace->set_flag) | |
3420 | ret = current_trace->set_flag(topt->flags->val, | |
3421 | topt->opt->bit, 1); | |
3422 | mutex_unlock(&trace_types_lock); | |
3423 | if (ret) | |
3424 | return ret; | |
3425 | topt->flags->val |= topt->opt->bit; | |
3426 | break; | |
3427 | ||
3428 | default: | |
3429 | return -EINVAL; | |
3430 | } | |
3431 | ||
3432 | *ppos += cnt; | |
3433 | ||
3434 | return cnt; | |
3435 | } | |
3436 | ||
3437 | ||
3438 | static const struct file_operations trace_options_fops = { | |
3439 | .open = tracing_open_generic, | |
3440 | .read = trace_options_read, | |
3441 | .write = trace_options_write, | |
3442 | }; | |
3443 | ||
a8259075 SR |
3444 | static ssize_t |
3445 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
3446 | loff_t *ppos) | |
3447 | { | |
3448 | long index = (long)filp->private_data; | |
3449 | char *buf; | |
3450 | ||
3451 | if (trace_flags & (1 << index)) | |
3452 | buf = "1\n"; | |
3453 | else | |
3454 | buf = "0\n"; | |
3455 | ||
3456 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
3457 | } | |
3458 | ||
3459 | static ssize_t | |
3460 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
3461 | loff_t *ppos) | |
3462 | { | |
3463 | long index = (long)filp->private_data; | |
3464 | char buf[64]; | |
3465 | unsigned long val; | |
3466 | int ret; | |
3467 | ||
3468 | if (cnt >= sizeof(buf)) | |
3469 | return -EINVAL; | |
3470 | ||
3471 | if (copy_from_user(&buf, ubuf, cnt)) | |
3472 | return -EFAULT; | |
3473 | ||
3474 | buf[cnt] = 0; | |
3475 | ||
3476 | ret = strict_strtoul(buf, 10, &val); | |
3477 | if (ret < 0) | |
3478 | return ret; | |
3479 | ||
3480 | switch (val) { | |
3481 | case 0: | |
3482 | trace_flags &= ~(1 << index); | |
3483 | break; | |
3484 | case 1: | |
3485 | trace_flags |= 1 << index; | |
3486 | break; | |
3487 | ||
3488 | default: | |
3489 | return -EINVAL; | |
3490 | } | |
3491 | ||
3492 | *ppos += cnt; | |
3493 | ||
3494 | return cnt; | |
3495 | } | |
3496 | ||
a8259075 SR |
3497 | static const struct file_operations trace_options_core_fops = { |
3498 | .open = tracing_open_generic, | |
3499 | .read = trace_options_core_read, | |
3500 | .write = trace_options_core_write, | |
3501 | }; | |
3502 | ||
3503 | static struct dentry *trace_options_init_dentry(void) | |
3504 | { | |
3505 | struct dentry *d_tracer; | |
3506 | static struct dentry *t_options; | |
3507 | ||
3508 | if (t_options) | |
3509 | return t_options; | |
3510 | ||
3511 | d_tracer = tracing_init_dentry(); | |
3512 | if (!d_tracer) | |
3513 | return NULL; | |
3514 | ||
3515 | t_options = debugfs_create_dir("options", d_tracer); | |
3516 | if (!t_options) { | |
3517 | pr_warning("Could not create debugfs directory 'options'\n"); | |
3518 | return NULL; | |
3519 | } | |
3520 | ||
3521 | return t_options; | |
3522 | } | |
3523 | ||
577b785f SR |
3524 | static void |
3525 | create_trace_option_file(struct trace_option_dentry *topt, | |
3526 | struct tracer_flags *flags, | |
3527 | struct tracer_opt *opt) | |
3528 | { | |
3529 | struct dentry *t_options; | |
3530 | struct dentry *entry; | |
3531 | ||
3532 | t_options = trace_options_init_dentry(); | |
3533 | if (!t_options) | |
3534 | return; | |
3535 | ||
3536 | topt->flags = flags; | |
3537 | topt->opt = opt; | |
3538 | ||
3539 | entry = debugfs_create_file(opt->name, 0644, t_options, topt, | |
3540 | &trace_options_fops); | |
3541 | ||
3542 | topt->entry = entry; | |
3543 | ||
3544 | } | |
3545 | ||
3546 | static struct trace_option_dentry * | |
3547 | create_trace_option_files(struct tracer *tracer) | |
3548 | { | |
3549 | struct trace_option_dentry *topts; | |
3550 | struct tracer_flags *flags; | |
3551 | struct tracer_opt *opts; | |
3552 | int cnt; | |
3553 | ||
3554 | if (!tracer) | |
3555 | return NULL; | |
3556 | ||
3557 | flags = tracer->flags; | |
3558 | ||
3559 | if (!flags || !flags->opts) | |
3560 | return NULL; | |
3561 | ||
3562 | opts = flags->opts; | |
3563 | ||
3564 | for (cnt = 0; opts[cnt].name; cnt++) | |
3565 | ; | |
3566 | ||
0cfe8245 | 3567 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f SR |
3568 | if (!topts) |
3569 | return NULL; | |
3570 | ||
3571 | for (cnt = 0; opts[cnt].name; cnt++) | |
3572 | create_trace_option_file(&topts[cnt], flags, | |
3573 | &opts[cnt]); | |
3574 | ||
3575 | return topts; | |
3576 | } | |
3577 | ||
3578 | static void | |
3579 | destroy_trace_option_files(struct trace_option_dentry *topts) | |
3580 | { | |
3581 | int cnt; | |
3582 | ||
3583 | if (!topts) | |
3584 | return; | |
3585 | ||
3586 | for (cnt = 0; topts[cnt].opt; cnt++) { | |
3587 | if (topts[cnt].entry) | |
3588 | debugfs_remove(topts[cnt].entry); | |
3589 | } | |
3590 | ||
3591 | kfree(topts); | |
3592 | } | |
3593 | ||
a8259075 SR |
3594 | static struct dentry * |
3595 | create_trace_option_core_file(const char *option, long index) | |
3596 | { | |
3597 | struct dentry *t_options; | |
3598 | struct dentry *entry; | |
3599 | ||
3600 | t_options = trace_options_init_dentry(); | |
3601 | if (!t_options) | |
3602 | return NULL; | |
3603 | ||
3604 | entry = debugfs_create_file(option, 0644, t_options, (void *)index, | |
3605 | &trace_options_core_fops); | |
3606 | ||
3607 | return entry; | |
3608 | } | |
3609 | ||
3610 | static __init void create_trace_options_dir(void) | |
3611 | { | |
3612 | struct dentry *t_options; | |
3613 | struct dentry *entry; | |
3614 | int i; | |
3615 | ||
3616 | t_options = trace_options_init_dentry(); | |
3617 | if (!t_options) | |
3618 | return; | |
3619 | ||
3620 | for (i = 0; trace_options[i]; i++) { | |
3621 | entry = create_trace_option_core_file(trace_options[i], i); | |
3622 | if (!entry) | |
3623 | pr_warning("Could not create debugfs %s entry\n", | |
3624 | trace_options[i]); | |
3625 | } | |
3626 | } | |
3627 | ||
b5ad384e | 3628 | static __init int tracer_init_debugfs(void) |
bc0c38d1 SR |
3629 | { |
3630 | struct dentry *d_tracer; | |
2cadf913 | 3631 | struct dentry *buffers; |
bc0c38d1 | 3632 | struct dentry *entry; |
b04cc6b1 | 3633 | int cpu; |
bc0c38d1 SR |
3634 | |
3635 | d_tracer = tracing_init_dentry(); | |
3636 | ||
3637 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
3638 | &global_trace, &tracing_ctrl_fops); | |
3639 | if (!entry) | |
3640 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
3641 | ||
ee6bce52 | 3642 | entry = debugfs_create_file("trace_options", 0644, d_tracer, |
bc0c38d1 SR |
3643 | NULL, &tracing_iter_fops); |
3644 | if (!entry) | |
ee6bce52 | 3645 | pr_warning("Could not create debugfs 'trace_options' entry\n"); |
bc0c38d1 | 3646 | |
a8259075 SR |
3647 | create_trace_options_dir(); |
3648 | ||
c7078de1 IM |
3649 | entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer, |
3650 | NULL, &tracing_cpumask_fops); | |
3651 | if (!entry) | |
3652 | pr_warning("Could not create debugfs 'tracing_cpumask' entry\n"); | |
3653 | ||
bc0c38d1 | 3654 | entry = debugfs_create_file("trace", 0444, d_tracer, |
b04cc6b1 | 3655 | (void *) TRACE_PIPE_ALL_CPU, &tracing_fops); |
bc0c38d1 SR |
3656 | if (!entry) |
3657 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
3658 | ||
3659 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
3660 | &global_trace, &show_traces_fops); | |
3661 | if (!entry) | |
98a983aa | 3662 | pr_warning("Could not create debugfs 'available_tracers' entry\n"); |
bc0c38d1 SR |
3663 | |
3664 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
3665 | &global_trace, &set_tracer_fops); | |
3666 | if (!entry) | |
98a983aa | 3667 | pr_warning("Could not create debugfs 'current_tracer' entry\n"); |
bc0c38d1 SR |
3668 | |
3669 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
3670 | &tracing_max_latency, | |
3671 | &tracing_max_lat_fops); | |
3672 | if (!entry) | |
3673 | pr_warning("Could not create debugfs " | |
3674 | "'tracing_max_latency' entry\n"); | |
3675 | ||
3676 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
3677 | &tracing_thresh, &tracing_max_lat_fops); | |
3678 | if (!entry) | |
3679 | pr_warning("Could not create debugfs " | |
98a983aa | 3680 | "'tracing_thresh' entry\n"); |
7bd2f24c IM |
3681 | entry = debugfs_create_file("README", 0644, d_tracer, |
3682 | NULL, &tracing_readme_fops); | |
3683 | if (!entry) | |
3684 | pr_warning("Could not create debugfs 'README' entry\n"); | |
3685 | ||
b04cc6b1 FW |
3686 | entry = debugfs_create_file("trace_pipe", 0444, d_tracer, |
3687 | (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops); | |
b3806b43 SR |
3688 | if (!entry) |
3689 | pr_warning("Could not create debugfs " | |
98a983aa | 3690 | "'trace_pipe' entry\n"); |
bc0c38d1 | 3691 | |
a94c80e7 | 3692 | entry = debugfs_create_file("buffer_size_kb", 0644, d_tracer, |
a98a3c3f SR |
3693 | &global_trace, &tracing_entries_fops); |
3694 | if (!entry) | |
3695 | pr_warning("Could not create debugfs " | |
a94c80e7 | 3696 | "'buffer_size_kb' entry\n"); |
a98a3c3f | 3697 | |
5bf9a1ee PP |
3698 | entry = debugfs_create_file("trace_marker", 0220, d_tracer, |
3699 | NULL, &tracing_mark_fops); | |
3700 | if (!entry) | |
3701 | pr_warning("Could not create debugfs " | |
3702 | "'trace_marker' entry\n"); | |
3703 | ||
2cadf913 SR |
3704 | buffers = debugfs_create_dir("binary_buffers", d_tracer); |
3705 | ||
3706 | if (!buffers) | |
3707 | pr_warning("Could not create buffers directory\n"); | |
3708 | else { | |
3709 | int cpu; | |
3710 | char buf[64]; | |
3711 | ||
3712 | for_each_tracing_cpu(cpu) { | |
3713 | sprintf(buf, "%d", cpu); | |
3714 | ||
3715 | entry = debugfs_create_file(buf, 0444, buffers, | |
3716 | (void *)(long)cpu, | |
3717 | &tracing_buffers_fops); | |
3718 | if (!entry) | |
3719 | pr_warning("Could not create debugfs buffers " | |
3720 | "'%s' entry\n", buf); | |
3721 | } | |
3722 | } | |
3723 | ||
bc0c38d1 SR |
3724 | #ifdef CONFIG_DYNAMIC_FTRACE |
3725 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
3726 | &ftrace_update_tot_cnt, | |
b807c3d0 | 3727 | &tracing_dyn_info_fops); |
bc0c38d1 SR |
3728 | if (!entry) |
3729 | pr_warning("Could not create debugfs " | |
3730 | "'dyn_ftrace_total_info' entry\n"); | |
3731 | #endif | |
d618b3e6 IM |
3732 | #ifdef CONFIG_SYSPROF_TRACER |
3733 | init_tracer_sysprof_debugfs(d_tracer); | |
3734 | #endif | |
b04cc6b1 FW |
3735 | |
3736 | for_each_tracing_cpu(cpu) | |
3737 | tracing_init_debugfs_percpu(cpu); | |
3738 | ||
b5ad384e | 3739 | return 0; |
bc0c38d1 SR |
3740 | } |
3741 | ||
1fd8f2a3 | 3742 | int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args) |
dd0e545f | 3743 | { |
efed792d | 3744 | static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED; |
dd0e545f | 3745 | static char trace_buf[TRACE_BUF_SIZE]; |
f09ce573 | 3746 | |
3928a8a2 | 3747 | struct ring_buffer_event *event; |
f09ce573 | 3748 | struct trace_array *tr = &global_trace; |
dd0e545f | 3749 | struct trace_array_cpu *data; |
38697053 | 3750 | int cpu, len = 0, size, pc; |
e726f5f9 IM |
3751 | struct print_entry *entry; |
3752 | unsigned long irq_flags; | |
dd0e545f | 3753 | |
8e1b82e0 | 3754 | if (tracing_disabled || tracing_selftest_running) |
dd0e545f SR |
3755 | return 0; |
3756 | ||
38697053 SR |
3757 | pc = preempt_count(); |
3758 | preempt_disable_notrace(); | |
dd0e545f SR |
3759 | cpu = raw_smp_processor_id(); |
3760 | data = tr->data[cpu]; | |
dd0e545f | 3761 | |
3ea2e6d7 | 3762 | if (unlikely(atomic_read(&data->disabled))) |
dd0e545f SR |
3763 | goto out; |
3764 | ||
380c4b14 | 3765 | pause_graph_tracing(); |
efed792d PZ |
3766 | raw_local_irq_save(irq_flags); |
3767 | __raw_spin_lock(&trace_buf_lock); | |
801fe400 | 3768 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args); |
dd0e545f SR |
3769 | |
3770 | len = min(len, TRACE_BUF_SIZE-1); | |
3771 | trace_buf[len] = 0; | |
3772 | ||
777e208d | 3773 | size = sizeof(*entry) + len + 1; |
51a763dd | 3774 | event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc); |
3928a8a2 SR |
3775 | if (!event) |
3776 | goto out_unlock; | |
777e208d | 3777 | entry = ring_buffer_event_data(event); |
777e208d | 3778 | entry->ip = ip; |
1fd8f2a3 | 3779 | entry->depth = depth; |
dd0e545f | 3780 | |
777e208d SR |
3781 | memcpy(&entry->buf, trace_buf, len); |
3782 | entry->buf[len] = 0; | |
0a987751 | 3783 | ring_buffer_unlock_commit(tr->buffer, event); |
dd0e545f | 3784 | |
3928a8a2 | 3785 | out_unlock: |
efed792d PZ |
3786 | __raw_spin_unlock(&trace_buf_lock); |
3787 | raw_local_irq_restore(irq_flags); | |
380c4b14 | 3788 | unpause_graph_tracing(); |
dd0e545f | 3789 | out: |
38697053 | 3790 | preempt_enable_notrace(); |
dd0e545f SR |
3791 | |
3792 | return len; | |
3793 | } | |
801fe400 PP |
3794 | EXPORT_SYMBOL_GPL(trace_vprintk); |
3795 | ||
3796 | int __ftrace_printk(unsigned long ip, const char *fmt, ...) | |
3797 | { | |
3798 | int ret; | |
3799 | va_list ap; | |
3800 | ||
3801 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
3802 | return 0; | |
3803 | ||
3804 | va_start(ap, fmt); | |
21a8c466 | 3805 | ret = trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap); |
801fe400 PP |
3806 | va_end(ap); |
3807 | return ret; | |
3808 | } | |
dd0e545f SR |
3809 | EXPORT_SYMBOL_GPL(__ftrace_printk); |
3810 | ||
9011262a ACM |
3811 | int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) |
3812 | { | |
3813 | if (!(trace_flags & TRACE_ITER_PRINTK)) | |
3814 | return 0; | |
3815 | ||
3816 | return trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap); | |
3817 | } | |
3818 | EXPORT_SYMBOL_GPL(__ftrace_vprintk); | |
3819 | ||
3f5a54e3 SR |
3820 | static int trace_panic_handler(struct notifier_block *this, |
3821 | unsigned long event, void *unused) | |
3822 | { | |
944ac425 SR |
3823 | if (ftrace_dump_on_oops) |
3824 | ftrace_dump(); | |
3f5a54e3 SR |
3825 | return NOTIFY_OK; |
3826 | } | |
3827 | ||
3828 | static struct notifier_block trace_panic_notifier = { | |
3829 | .notifier_call = trace_panic_handler, | |
3830 | .next = NULL, | |
3831 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
3832 | }; | |
3833 | ||
3834 | static int trace_die_handler(struct notifier_block *self, | |
3835 | unsigned long val, | |
3836 | void *data) | |
3837 | { | |
3838 | switch (val) { | |
3839 | case DIE_OOPS: | |
944ac425 SR |
3840 | if (ftrace_dump_on_oops) |
3841 | ftrace_dump(); | |
3f5a54e3 SR |
3842 | break; |
3843 | default: | |
3844 | break; | |
3845 | } | |
3846 | return NOTIFY_OK; | |
3847 | } | |
3848 | ||
3849 | static struct notifier_block trace_die_notifier = { | |
3850 | .notifier_call = trace_die_handler, | |
3851 | .priority = 200 | |
3852 | }; | |
3853 | ||
3854 | /* | |
3855 | * printk is set to max of 1024, we really don't need it that big. | |
3856 | * Nothing should be printing 1000 characters anyway. | |
3857 | */ | |
3858 | #define TRACE_MAX_PRINT 1000 | |
3859 | ||
3860 | /* | |
3861 | * Define here KERN_TRACE so that we have one place to modify | |
3862 | * it if we decide to change what log level the ftrace dump | |
3863 | * should be at. | |
3864 | */ | |
428aee14 | 3865 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 SR |
3866 | |
3867 | static void | |
3868 | trace_printk_seq(struct trace_seq *s) | |
3869 | { | |
3870 | /* Probably should print a warning here. */ | |
3871 | if (s->len >= 1000) | |
3872 | s->len = 1000; | |
3873 | ||
3874 | /* should be zero ended, but we are paranoid. */ | |
3875 | s->buffer[s->len] = 0; | |
3876 | ||
3877 | printk(KERN_TRACE "%s", s->buffer); | |
3878 | ||
f9520750 | 3879 | trace_seq_init(s); |
3f5a54e3 SR |
3880 | } |
3881 | ||
3f5a54e3 SR |
3882 | void ftrace_dump(void) |
3883 | { | |
3884 | static DEFINE_SPINLOCK(ftrace_dump_lock); | |
3885 | /* use static because iter can be a bit big for the stack */ | |
3886 | static struct trace_iterator iter; | |
3f5a54e3 | 3887 | static int dump_ran; |
d769041f SR |
3888 | unsigned long flags; |
3889 | int cnt = 0, cpu; | |
3f5a54e3 SR |
3890 | |
3891 | /* only one dump */ | |
3892 | spin_lock_irqsave(&ftrace_dump_lock, flags); | |
3893 | if (dump_ran) | |
3894 | goto out; | |
3895 | ||
3896 | dump_ran = 1; | |
3897 | ||
3898 | /* No turning back! */ | |
0ee6b6cf | 3899 | tracing_off(); |
81adbdc0 | 3900 | ftrace_kill(); |
3f5a54e3 | 3901 | |
d769041f SR |
3902 | for_each_tracing_cpu(cpu) { |
3903 | atomic_inc(&global_trace.data[cpu]->disabled); | |
3904 | } | |
3905 | ||
b54d3de9 TE |
3906 | /* don't look at user memory in panic mode */ |
3907 | trace_flags &= ~TRACE_ITER_SYM_USEROBJ; | |
3908 | ||
3f5a54e3 SR |
3909 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); |
3910 | ||
e543ad76 | 3911 | /* Simulate the iterator */ |
3f5a54e3 SR |
3912 | iter.tr = &global_trace; |
3913 | iter.trace = current_trace; | |
e543ad76 | 3914 | iter.cpu_file = TRACE_PIPE_ALL_CPU; |
3f5a54e3 SR |
3915 | |
3916 | /* | |
3917 | * We need to stop all tracing on all CPUS to read the | |
3918 | * the next buffer. This is a bit expensive, but is | |
3919 | * not done often. We fill all what we can read, | |
3920 | * and then release the locks again. | |
3921 | */ | |
3922 | ||
3f5a54e3 SR |
3923 | while (!trace_empty(&iter)) { |
3924 | ||
3925 | if (!cnt) | |
3926 | printk(KERN_TRACE "---------------------------------\n"); | |
3927 | ||
3928 | cnt++; | |
3929 | ||
3930 | /* reset all but tr, trace, and overruns */ | |
3931 | memset(&iter.seq, 0, | |
3932 | sizeof(struct trace_iterator) - | |
3933 | offsetof(struct trace_iterator, seq)); | |
3934 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
3935 | iter.pos = -1; | |
3936 | ||
3937 | if (find_next_entry_inc(&iter) != NULL) { | |
3938 | print_trace_line(&iter); | |
3939 | trace_consume(&iter); | |
3940 | } | |
3941 | ||
3942 | trace_printk_seq(&iter.seq); | |
3943 | } | |
3944 | ||
3945 | if (!cnt) | |
3946 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
3947 | else | |
3948 | printk(KERN_TRACE "---------------------------------\n"); | |
3949 | ||
3f5a54e3 SR |
3950 | out: |
3951 | spin_unlock_irqrestore(&ftrace_dump_lock, flags); | |
3952 | } | |
3953 | ||
3928a8a2 | 3954 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 3955 | { |
4c11d7ae | 3956 | struct trace_array_cpu *data; |
4c11d7ae | 3957 | int i; |
9e01c1b7 | 3958 | int ret = -ENOMEM; |
4c11d7ae | 3959 | |
9e01c1b7 RR |
3960 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
3961 | goto out; | |
3962 | ||
3963 | if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL)) | |
3964 | goto out_free_buffer_mask; | |
4c11d7ae | 3965 | |
b04cc6b1 FW |
3966 | if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL)) |
3967 | goto out_free_tracing_cpumask; | |
3968 | ||
9e01c1b7 RR |
3969 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
3970 | cpumask_copy(tracing_cpumask, cpu_all_mask); | |
b04cc6b1 | 3971 | cpumask_clear(tracing_reader_cpumask); |
9e01c1b7 RR |
3972 | |
3973 | /* TODO: make the number of buffers hot pluggable with CPUS */ | |
3928a8a2 SR |
3974 | global_trace.buffer = ring_buffer_alloc(trace_buf_size, |
3975 | TRACE_BUFFER_FLAGS); | |
3976 | if (!global_trace.buffer) { | |
3977 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); | |
3978 | WARN_ON(1); | |
9e01c1b7 | 3979 | goto out_free_cpumask; |
4c11d7ae | 3980 | } |
3928a8a2 | 3981 | global_trace.entries = ring_buffer_size(global_trace.buffer); |
4c11d7ae | 3982 | |
9e01c1b7 | 3983 | |
4c11d7ae | 3984 | #ifdef CONFIG_TRACER_MAX_TRACE |
3928a8a2 SR |
3985 | max_tr.buffer = ring_buffer_alloc(trace_buf_size, |
3986 | TRACE_BUFFER_FLAGS); | |
3987 | if (!max_tr.buffer) { | |
3988 | printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n"); | |
3989 | WARN_ON(1); | |
3990 | ring_buffer_free(global_trace.buffer); | |
9e01c1b7 | 3991 | goto out_free_cpumask; |
4c11d7ae | 3992 | } |
3928a8a2 SR |
3993 | max_tr.entries = ring_buffer_size(max_tr.buffer); |
3994 | WARN_ON(max_tr.entries != global_trace.entries); | |
a98a3c3f | 3995 | #endif |
ab46428c | 3996 | |
4c11d7ae | 3997 | /* Allocate the first page for all buffers */ |
ab46428c | 3998 | for_each_tracing_cpu(i) { |
4c11d7ae | 3999 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 | 4000 | max_tr.data[i] = &per_cpu(max_data, i); |
4c11d7ae | 4001 | } |
bc0c38d1 | 4002 | |
bc0c38d1 SR |
4003 | trace_init_cmdlines(); |
4004 | ||
43a15386 | 4005 | register_tracer(&nop_trace); |
79fb0768 | 4006 | current_trace = &nop_trace; |
b5ad384e FW |
4007 | #ifdef CONFIG_BOOT_TRACER |
4008 | register_tracer(&boot_tracer); | |
b5ad384e | 4009 | #endif |
60a11774 SR |
4010 | /* All seems OK, enable tracing */ |
4011 | tracing_disabled = 0; | |
3928a8a2 | 4012 | |
3f5a54e3 SR |
4013 | atomic_notifier_chain_register(&panic_notifier_list, |
4014 | &trace_panic_notifier); | |
4015 | ||
4016 | register_die_notifier(&trace_die_notifier); | |
9e01c1b7 | 4017 | ret = 0; |
3f5a54e3 | 4018 | |
9e01c1b7 | 4019 | out_free_cpumask: |
b04cc6b1 FW |
4020 | free_cpumask_var(tracing_reader_cpumask); |
4021 | out_free_tracing_cpumask: | |
9e01c1b7 RR |
4022 | free_cpumask_var(tracing_cpumask); |
4023 | out_free_buffer_mask: | |
4024 | free_cpumask_var(tracing_buffer_mask); | |
4025 | out: | |
4026 | return ret; | |
bc0c38d1 | 4027 | } |
b2821ae6 SR |
4028 | |
4029 | __init static int clear_boot_tracer(void) | |
4030 | { | |
4031 | /* | |
4032 | * The default tracer at boot buffer is an init section. | |
4033 | * This function is called in lateinit. If we did not | |
4034 | * find the boot tracer, then clear it out, to prevent | |
4035 | * later registration from accessing the buffer that is | |
4036 | * about to be freed. | |
4037 | */ | |
4038 | if (!default_bootup_tracer) | |
4039 | return 0; | |
4040 | ||
4041 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
4042 | default_bootup_tracer); | |
4043 | default_bootup_tracer = NULL; | |
4044 | ||
4045 | return 0; | |
4046 | } | |
4047 | ||
b5ad384e FW |
4048 | early_initcall(tracer_alloc_buffers); |
4049 | fs_initcall(tracer_init_debugfs); | |
b2821ae6 | 4050 | late_initcall(clear_boot_tracer); |